Herbicide composition comprising herbicide compound in acid form and acidifying agent

ABSTRACT

Described are herbicide compositions and methods for their preparation and use, in particular, herbicide compositions and methods relating to herbicide compositions containing herbicide compounds in acid form, and further including an acidifying agent.

This application claims the benefit of U.S. patent application Ser. No.10/102,799, filed Mar. 21, 2002, which claims the benefit of U.S.Provisional Application Ser. No. 60/325,289, U.S. ProvisionalApplication Ser. No. 60/325,342, and U.S. Provisional Application Ser.No. 60/325,343, all filed Sep. 26, 2001, and the benefit of U.S.Provisional Application Ser. No. 60/361,016, filed Feb. 28, 2002.

FIELD OF THE INVENTION

The invention relates to herbicide compositions and their preparationand use, and in particular to herbicide compositions and methodsrelating to herbicide compositions containing herbicide compounds inacid form, and further including an acidifying agent.

BACKGROUND

Commercially available herbicide compositions include a very largevariety of active herbicide compounds. Such herbicide compositions canbe prepared from different types of precursor compositions, and can becommercially available and used in a variety of different types ofcompositions, including, for example, compositions referred to aswettable powders, water dispersible granules, granules, aqueoussolutions, water soluble powders, emulsifiable concentrates, oil-basedflowables, concentrated emulsions, suspo-emulsions, emulsions,suspensions, suspension concentrates, mixtures, dispersions, andmicroemulsions, as well as others. Any of these different types ofcompositions may have different advantages or disadvantages relating tofactors such as the mode of application and the type of activeingredient included in the herbicide composition.

Examples of just a few available active herbicide compounds includethose of the general class known as phenoxy herbicides, e.g.,2,4-dichlorophenoxyacetic acid (known as 2,4-D), MCPA acid, MCPP acid;those of the general class known as pyridine herbicides, (e.g.,triclopyr, fluoroxypyr); those of the general class of benzoic acidherbicides, (e.g., dicamba acid); those of the general class of aryloxyphenoxy propionic acid herbicides, (e.g., fluazifop acid and quizolofopacid); water-insoluble diphenyl ether type herbicides (e.g., oxyfluorfenor acifluorfen); glyphosate compounds (N-(phosphonomethyl)glycine),e.g., in the acid form, referred to as glyphosate acid, or in a saltform such as the IPA salt form; imidizole herbicide compounds (e.g.,imazapyr or imazaquin); as well as others. Often, salt and ester formsof herbicide compounds tend to be more soluble in water and arepreferentially chosen for use over acid forms of herbicide compositions.

A specific class of sulfuric acid adduct is described in U.S. Pat. Nos.4,445,925, 4,994,101, and 5,288,692, (to Young) as useful with certainherbicide compounds.

New forms of useful or improved herbicide compositions are alwaysdesirable, especially those that show advantages in processing,application, environmental profile (e.g., volatility), or efficacy.

SUMMARY OF THE INVENTION

The invention relates to herbicide compositions for controlling plantgrowth, wherein the herbicide composition includes a herbicide compoundin acid form, and also further includes an acidifying agent. Preferably,the herbicide composition, as applied, has a pH that is below the pKa ofthe herbicide compound.

The herbicide composition can be prepared from precursor ingredientssuch as microemulsion-forming concentrates, microemulsions, suspensionconcentrates, or any other type or form of herbicide compositions orherbicide precursor composition or concentrate. Acidifying agent can beadded to the herbicide composition at any stage of processing,preparation, or use. The herbicide compound in acid form can be anyherbicide compound known to exist in an acid form. And the acidifyingagent can be any acidifying agent capable of reducing the pH of theherbicide composition, preferably to an acidic pH and most preferably toa pH below the pKa of the herbicide compound.

While others such as Young have included sulfuric acid adducts inherbicide compositions with certain herbicide compounds, otheracidifying agents have now been discovered to be useful and even providebenefits such as improved efficacy. Also, additional benefits can occurin particular upon applying a herbicide composition that includes aherbicide compound in the acid form as opposed to other forms such asester forms or salt forms.

An aspect of the invention relates to a herbicide composition comprisinga herbicide compound in acid form and an acidifying agent, wherein theherbicide compound in acid form is other than glyphosate acid.

Another aspect of the invention relates to a herbicide compositioncomprising a herbicide compound in acid form selected from the groupconsisting of: a phenoxy herbicide, a pyridine herbicide, a benzoic acidherbicide, a quinolinic acid herbicide, an aryloxy phenoxy propionicacid herbicide, and combinations thereof, and wherein the herbicidecomposition includes an acidifying agent.

Another aspect of the invention relates to a herbicide compositioncomprising a herbicide compound in acid form and an acidifying agent,wherein the acidifying agent is selected from the group consisting of:sulfuric acid, hydrochloric acid, nitric acid, acetic acid, phosphoricacid, perchloric acid, polyphosphoric acid, and combinations thereof,and the herbicide composition does not include an adduct of sulfuricacid and a compound of the formula:

wherein X is chalcogen, and each of R₁, R₂, and R ₃ is independentlyselected from hydrogen and organic radicals.

Another aspect of the invention relates to a herbicide compositioncomprising herbicide compound in acid form and an acidifying agent,wherein the acidifying agent is other than an acidifying agent selectedfrom the group consisting of sulfuric acid; an adduct of sulfuric acidand a compound of the formula:

wherein X is chalcogen, and each of R₁, R₂, and R ₃ is independentlyselected from hydrogen and organic radicals; and mixtures thereof.

Another aspect of the invention relates to a herbicide compositioncomprising a formulation selected from the group consisting of amicroemulsion-forming-concentrate that contains a herbicide compound inacid form and a microemulsion that contains a herbicide compound in acidform, the herbicide composition comprising an acidifying agent.

Yet another aspect of the invention relates to a method of applying aherbicide composition. The method comprises preparing a herbicidecomposition comprising herbicide compound in acid form and acidifyingagent, wherein the herbicide compound in acid form is other thanglyphosate acid. The herbicide composition comprising the herbicidecompound in acid form and acidifying agent is applied to control plantgrowth.

Another aspect of the invention relates to a method of applying aherbicide composition. The method comprises preparing a herbicidecomposition comprising herbicide compound in acid form and acidifyingagent, wherein the herbicide compound in acid form selected from thegroup consisting of: a phenoxy herbicide, a pyridine herbicide, abenzoic acid herbicide, a quinolinic acid herbicide, an aryloxy phenoxypropionic acid herbicide, and combinations thereof. The herbicidecomposition comprising the herbicide compound in acid form andacidifying agent is applied to control plant growth.

DETAILED DESCRIPTION

Herbicide compositions of the invention include a herbicide compound inits acid form and an acidifying agent. The term “herbicide composition”refers to a composition that includes a herbicide compound, including(as will be described in more detail below) microemulsion-formingconcentrates or microemulsions, derivatives thereof, suspensionconcentrates and derivatives thereof, and any other liquid or solid formcomposition that includes a herbicide compound. Other examples mayinclude wettable powders, water dispersible granules, other types ofgranules, water-soluble powders, emulsifiable concentrates, oil-basedflowables, concentrated emulsions, suspo-emulsions, emulsions,suspensions, mixtures, dispersions, and derivatives of any of these andothers, any of which include a herbicide compound in acid form, and canfurther include or be combined with acidifying agent.

Different classes of herbicide compounds and different specificherbicide compounds within these classes can be used to prepareherbicide compositions according to the invention. A large variety ofherbicide compounds are well known and commercially available, and oneof skill will be able to identify herbicide compounds useful accordingto the invention, based on the present description. Suitable herbicidecompounds can include herbicide compounds that act as pre-emergent orpost-emergent systemic herbicides, and that can exist in an acid form.Compositions and methods of the invention are particularly beneficialwhen using herbicides having post-emergent activity, i.e., systemicherbicidal activity toward established plants, due to the improvementsin post-emergent, systemic activity available with these compositionsand methods. While wishing not to be bound by theory, it is believedthat the use of a herbicide compound in acid form, especially applieddirectly to a plant, and especially in a herbicide composition having anacidic and a relatively low pH (e.g., below 7, 6, or 5, or below the pKaof a herbicide compound, or lower) can effect improvements in plantcontrol by one or both of the following mechanisms. First, acharge-neutral molecule (such as an acid) can have an easier timepenetrating a cuticle on a plant compared to a charged molecule (e.g.,salt). Secondly, when the herbicide compound in acid form is appliedwith a herbicide composition containing an acidifying agent and at a lowpH, the acidifying agent and low pH can have a damaging effect on aplant's surface, thereby allowing more herbicide compound to penetratethe plant surface. Separately, acid forms of herbicide compounds, due totheir uncharged state, can be advantageously less affected or unaffectedby hard water, e.g., less susceptible to de-activation by hard water.

Herbicide compounds may typically be available in ester or salt forms,and many herbicide compositions are conventionally sold commercially ineither a salt or ester form, which are often considered to be relativelysoluble, dispersible, or emulsifiable in water, as opposed to acid formswhich are often less soluble in water. Acid forms of herbicides are usedaccording to the invention.

“Herbicide compound in acid form,” as used herein, refers to a herbicidecompound that exists in a form of the compound that is considered to bethe “acid” form of the compound, as opposed to a different chemical formof the same compound such as a salt or an ester form. Many herbicidecompounds are capable of existing in discernible, understood, chemicallydifferent forms, including, e.g., an acid form, an ester form, or a saltform. The term “herbicide compound in acid form” includes herbicidecompounds of these types, when the compound is in the acid as opposed toan ester or a salt form.

One way of identifying a herbicide compound in acid form is to referencea pKa of a herbicide compound. The pKa of a herbicide compound isunderstood to refer to the negative logarithm (base 10) of theequilibrium constant K for the reaction of the herbicide compoundbetween its acid form and its neutral form. Methods of determining thepKa for a herbicide compound will be readily understood by the skilledartisan. Exemplary herbicide compounds that are capable of existing inan acid form can have a pKa below about 6, or below about 5 or 4. Someherbicide compounds include more than one acidic hydrogen and thereforehave more than a single pKa value. According to the invention, therelevant and referred to pKa is the pKa of a herbicide compound thatrelates to the change of the compound between the compound considered tobe the deprotonated “acid” form of the compound, and what is consideredto be the protonated (neutral) form of the “acid.” The deprotonated acidform of the compound predominates at pH below the pKa, and theprotonated form predominates at pH above the pKa. Examples of pKa valuesfor certain herbicide compounds are included in the Table 1.

Some examples of useful herbicide compounds that can be used in theiracid forms according to the invention include the following, some or allof which are commercially available in their acid form (though presentlynot generally sold in that form as herbicide formulations). Forherbicide compounds that are sold in forms other than the acid form,such as a salt or ester form, a skilled chemist will understand how toconvert the non-acid to an acid form for use as described herein.

The class of phenoxy herbicides generally includes herbicides derivedfrom chlorinated phenols, and includes herbicide compounds that canexist in an acid form. Examples include the well known herbicides2,4-dichlorophenoxyacetic acid (known as 2,4-D),4-methyl4-chlorophenoxyacetic acid (MCPA Acid), and2(-2-methyl-4-chlorophenoxy)propionic acid (MCPP acid), as well asothers.

Pyridine herbicides are herbicides derived from a pyridinering-containing compound, and include herbicide compounds that can existin an acid form. Examples include 3,5,6-trichloro-2-pyridyloxyaceticacid (triclopyr acid) and fluroxypyr(4-amino-3,5-dichloro-6-fluoro-2-pyridyloxyacetic acid), as well asothers.

Benzoic acid herbicide compounds include or are derived from benzoicacid compounds. This class of herbicide compounds includes herbicidecompounds that can exist in an acid form. A single example is dicambaacid (3,6-dichloro-O-anisic acid), but others could also be usedaccording to the invention.

Aryloxy phenoxy propionic acid herbicide compounds (also referred tosometimes as “oxyphenoxy” herbicides), are another class of herbicidethat can exist in an acid form. Examples of specific compounds includefluazifop acid, quizolofop acid, as well as others.

Imidazolinones are still another class of herbicide compounds that canexist in acid form, with specific examples including imazethapyr acid,imazaquin acid, imazapyr acid, imazamethbenz acid, imazapic acid, andimazamox acid. See infra. TABLE 1 Acidic Herbicide pKas Trade Name SaltForm Herbicide Family Sub Family Bromoxynil 4.06 BUTRIL Benzonitrileloxynil 3.96 Benzonitrile Bentazon NA BASAGRAN sodium Non-Family Dicamba1.87 BANVEL diglycolamine Growth Regulator Bezoic Acid diethylamineDiclofop 3.57 HOELON Aryloxyphenoxy- propionate Fenoxaprop NA PUMAAryloxyphenoxy- propionate Fluazifop-p 2.98 FUSILADE Aryloxyphenoxy-propionate Fosamine NA KRENITE Non-Family Glufosinate 2, 2.9 LIBERTYammonium Phosphorylated amino acid Glyphosate 2.6, 5.6 ROUNDUPIsoproplyamine Non-Family Haloxyfop 4.33 VERDICT Aryloxyphenoxy-propionate Imazamethbenz 2.9 ASSERT Imidazolinone Imazapyr 2, 3 ARSENALIsoproplyamine Imidazolinone Imazaquin 3.8 SCEPTER ammoniumImidazolinone Imazamox RAPTOR Imidazolinone Imazethapyr 3.9 PURSUITammonium Imidazolinone Picloram 2.3 TORDON triisopropanolamine GrowthRegulator Pyridine Triclopyr 2.68 GARLON triethylamine Growth RegulatorPyridine Clopyralid 2.3 STINGER monoethanolamine Growth RegulatorPyridine Floroxypyr STARANE Growth Regulator Pyridine Quinclorac 4.34FACET Growth Regulator Quinolinic Acid Quizalofop-p NA ASSUREAryloxyphenoxy- propionate Sethoxydim 4.16 POAST Cyclohexanedione 2,4-D2.8 sodium Growth Regulator Phenoxy Carboxylic ammonium triethanolaminedimethylamine 2,4-DB 4.8 Phenoxy Carboxylic Dichlorprop 2.86dimethylamine Growth Regulator Phenoxy Carboxylic MCPA Growth RegulatorPhenoxy Carboxylic Mecoprop Growth Regulator Phenoxy (MCPP) CarboxylicClethodim SELECT Cyclohexanedione Sethoxydim Acifluorfen 3.86 BLAZERsodium Diphenyl Ether Dacthal Phthalic Acid Endothal Phthalic AcidAlanap Phthalic Acid Asulam 4.82 Non-Family(Where a pKa is not included, the skilled artisan will be able todetermine pKa.)

The herbicide compositions of the invention also include an acidifyingagent. The acidifying agent can be any acidic material that can be usedto reduce the pH of the herbicide composition and preferably maintainthe pH at a level that will allow the herbicide compound to exist in itsacid form, e.g., at a pH below 7, preferably below the pKa of theherbicide compound.

A variety of different acidifying agents can be useful in the herbicidecompositions of the invention, e.g., to improve efficacy of a herbicidecomposition. Examples of a certain type of acidifying agent aredescribed in U.S. Pat. Nos. 4,445,925, 4,994,101, 5,288,692, (to Young)the disclosures of which are incorporated herein by reference. Otherexemplary acidifying agents are known, and still others are describedherein, as well as in Assignee's U.S. patent application Ser. No.10/103,493, filed Mar. 21, 2002, entitled HERBICIDE COMPOSITIONSCOMPRISING SUSPENSION CONCENTRATE WITH GLYPHOSATE ACID, METHODS OFPREPARATION, AND METHODS OF USE, and U.S. Pat. No. 6,803,345, grantedOct. 12, 2004, entitled HERBICIDE MICROEMULSION-FORMING-CONCENTRATES,MICROEMULSIONS, AND METHODS, each of which is incorporated herein byreference.

The acidifying agent chosen and the amount included in a herbicidecomposition can be based on factors such as the intended application(including the identity of the undesirable plant growth, and the desiredplant growth), the method of application, the herbicide compound chosenand the type of herbicide application composition, physical and chemicalproperties of the herbicide application composition, and other factors.The acidifying agent may be any of a variety of suitable organic andinorganic acids, of any useful strength or concentration (e.g.,concentrated or diluted), that can be included in a herbicidecomposition, preferably without causing substantial or undue negativeeffects on the herbicide composition such as reaction with anotheringredient of the composition such as the herbicide compound,precipitation, etc.

Non-limiting examples of specifically useful acidifying agents includeacids such as sulfuric acid, phosphoric acid, hydrochloric acid, nitricacid, acetic acid (e.g., “glacial” acidic acid), perchloric acid,polyphosphoric acid, acidic adducts such as the sulfuric acid adductsdescribed in U.S. Pat. No. 5,288,692 (Young), especially the adduct ofsulfuric acid and urea, and any other composition that can be used toaffect the pH of a herbicide composition. It will be understood thatsuch acidifying agents can be used alone or in combination, and can beincluded in a herbicide composition in a concentrated or a diluted form.

Just one example of a useful class of acidifying agent is the class ofadducts of sulfuric acid and an “amide” according to the formula:

wherein X is chalcogen, and each of R₁, R₂, and R ₃ is independentlyselected from hydrogen and organic radicals. As used herein, “amide”encompasses all compounds of formula (1) regardless of the chalcogen.The molar ratio of amide to acid is usually in the range of about ¼ toless than 2 so that at least some of the acid is present as themonoamide-acid adduct.

When R₁, R₂, and R₃ are organic radicals, they may be cyclic or acyclic,straight, or branched chained, and can contain one or more heteroatomssuch as sulfur, nitrogen, oxygen, phosphorus and the like. Further, R₁,R₂, and R₃ can contain one or more substituents such as thiol, hydroxy,nitro, amino, nitrile, amide, ester and halogen groups and others. Suchorganic radicals may contain aryl groups such as aralkyl and alkarylgroups. Certain preferred organic radicals can be free of olefinic oralkynyl unsaturation and can generally have up to about 20, preferablyup to about 10 carbon atoms. Particularly preferred amides include urea,thiourea, formamide, dimethylformamide, biuret, triuret, thioformamide,and combinations of these.

The chalcogens are elements of Periodic Group VI-B and include oxygen,sulfur, selenium, tellurium, and polonium. Oxygen and sulfur can bepreferred due to low cost, availability, low toxicity, and chemicalactivity, and oxygen is the most preferred.

An example of a specific compound of formula (1) is the sulfuricacid/urea adduct:

Other types of useful acidifying agents, as stated, include sulfuricacid, phosphoric acid, hydrochloric acid, nitric acid, acetic acid(e.g., “glacial” acidic acid), perchloric acid, polyphosphoric acid,other adducts, etc. Various such acids are commercially available indifferent forms and concentrations, including solids, liquid solutions,concentrated or diluted liquid solutions, etc., or can be prepared byone of skill. Any such form of acidifying agent may be useful to reducethe pH of a herbicide composition, preferably without causing unduenegative effects on the herbicide composition. The chosen form of anacidifying agent may be based on factors such as commercialavailability, convenience, and the overall desired properties of theherbicide composition, its different ingredients (e.g., the herbicidecompound), and desired methods of preparation and use.

The particular amount of acidifying agent included in a herbicidecomposition can be selected depending on factors such as the particularcomposition and chemistry of the herbicide application composition,including the amounts and chemistries of other ingredients of thecompositions such as surfactants and the herbicide compound; the amountand identity of any solvent; whether water is included and in whatamount; the type of acidifying agent and its chemistry, form (e.g.,liquid, solid, concentrated, or diluted) and strength (concentration);and the desired pH of the herbicide composition and the relevant pKa ofthe herbicide compound. Preferred amounts of any particular acidifyingagent can be capable of improving the efficacy of a herbicidecomposition, and will be sufficient to produce an applicationcomposition having a pH below the pKa of the herbicide compound, asdiscussed.

The herbicide composition may be prepared from various differentherbicide compositions and herbicide composition precursors orconcentrates. Generally, the herbicide compositions of the invention canbe prepared from any type of precursor herbicide compositions.Non-limiting examples of herbicide composition precursors includemicroemulsion-forming concentrates or microemulsions and derivativesthereof, and suspension concentrates and derivatives thereof. Otherexamples may include wettable powders, water dispersible granules, othertypes of granules, water-soluble powders, emulsifiable concentrates,oil-based flowables, concentrated emulsions, suspo-emulsions, emulsions,suspensions, mixtures, dispersions, the derivatives of any of these andothers. Any of these or other types of herbicide compositions,precursors, or concentrates, can be used in manners known in herbicideand chemical arts, in combination with an acidifying agent according tothe invention. A couple of preferred methods of preparing herbicidecompositions according to the invention include preparation frommicroemulsion-forming-concentrates, microemulsions, and suspensionconcentrates, combined with acidifying agent. As will be readilyapparent to those skilled in the herbicide arts, however, and as statedabove and elsewhere in the present description, other types of herbicidecompositions, herbicide composition precursors, and concentrates, willbe useful when combined with acidifying agent according to the inventionand present description.

One method of preparing herbicide compositions of the invention is frommicroemulsions or microemulsion-forming-concentrates. See, Applicants'U.S. Pat. No. 6,803,345 entitled “HerbicideMicroemulsion-Forming-Concentrates, Microemulsions, and Methods.”

The term “microemulsion” means a solution that contains an oil phase andwater, wherein the oil phase is finely dispersed such that light passesthrough the microemulsion solution and the microemulsion may be opaqueor clear in appearance. Microemulsions are known types of compositions,and are sometimes considered either as micellar solutions containinginverted micelles (hydrophobic tails oriented toward the external oilphase and hydrophilic heads in the inner core) with water solubilized inthe inner core, or as emulsions containing tiny droplets of watersurrounded by an interfacial film. See, e.g., Surfactants andInterfacial Phenomena, Milton J. Rosen, Page 239&240, John Wiley & Sons(1978). Microemulsion-forming-concentrates or “MFCs” include a herbicidecompound (in acid form) dissolved in surfactant, optionally water,optionally may but preferably do not include added organic solvent, andcan be diluted with water to form a microemulsion. MFCs can typically betranslucent, opaque, or even clear solutions.

The herbicide compound in acid form can be dissolved in surfactant (andoptionally water and organic acid) to form an MFC that containssurfactant and dissolved herbicide compound in acid form.

A very large variety of surfactants are known and commerciallyavailable, including such different classes as cationic surfactants,anionic surfactants, non-ionic surfactants, ionic surfactants, andamphoteric surfactants. The surfactant can be any surfactant orcombination of two or more surfactants useful to dissolve the herbicidecompound in its acid form. Examples of some preferred surfactantsinclude cationic, non-ionic, and anionic surfactants. Of these, someeven more specific types of preferred surfactants include non-ioniclinear or branched alcohol ethoxylate surfactants, anionic phosphoricacid ester surfactants (sometimes referred to as “phosphate ester”surfactants), and cationic ethoxylated tallow amine surfactants.Examples of surfactants and identification of their intermediate andgeneral classifications are as follows: SURFACTANTS INTERMEDIATE GENERALTRADE NAME COMMON NAME CLASSIFICATION CLASSIFICATION Tomadol 1-5 11carbon 5 mole linear alcohol ethoxylated linear alcohol nonionic Tomadol1-7 11 carbon 7 mole linear alcohol ethoxylated linear alcohol nonionicSurfonic L12-6 12 carbon 6 mole linear alcohol ethoxylated linearalcohol nonionic Trymeen 6607 20 mole tallow amine ethoxylatedamines/amide cationic Stepfac 8170 phosphate ester phosphate esteranionic Surfonic PE 1218 phosphate ester phosphate ester anionicSurfonic DDA6  6 mole branched alcohol ethoxylate branched alcoholethoxylate nonionic Surfonic TDA6  6 mole tridecyl alcohol branchedalcohol ethoxylate nonionic Surfonic T-15 20 mole tallow amineethoxylated amines/amide cationic Surfonic OP-70  7 mole octylphenolethoxylated alkyl phenol nonionic Tergitol NP-6  6 mole nonylphenolethoxylated alkyl phenol nonionic Trylox 5902 16 mole castor oilethoxylated fatty acids/oils nonionic Span 80 sorbitan laurate sorbitanlaurate nonionic Tween 80 polysorbate 80 sorbitan oleate nonionicSoprophor 796P tristerol phenol EO/PO propylated, ethoxylated nonionicfatty acid, alcohols, or alkyl phenols Surfonic L24-5 24 carbon 5 molelinear alcohol ethoxylated linear alcohol nonionic

An anionic surfactant is a surface-active molecule in which an activeportion of a lipophilic portion of the molecule forms a negative ion(i.e., anion) when placed in aqueous solution. Exemplary anionicsurfactants include phosphoric acid ester surfactants (sometimesreferred to as “phosphate ester” surfactants), sodium alkyl naphthalenesulfonate surfactants, and ethoxylated tristyrylphenol phosphate salts.

Exemplary sodium alkyl naphthalene sulfonate surfactants include sodiumbutyl naphthalene sulfonate, sodium di-n-butyl naphthalene sulfonate,sodium diisopropyl naphthalene sulfonate, sodium dimethyl naphthalenesulfonate, and mixtures thereof. Sodium butyl naphthalene sulfonate iscommercially available, for example, under the trade name “MORWET B”from Witco/Crompton, Greenwich, Conn. Sodium di-n-butyl naphthalenesulfonate is commercially available, for example, under the trade name“MORWET DB” from Witco/Crompton, Greenwich, Conn. Sodium diisopropylnaphthalene sulfonate is commercially available, for example, under thetrade name “MORWET IP” from Witco/Crompton, Greenwich, Conn. Sodiumdimethyl naphthalene sulfonate surfactant is commercially available, forexample, under the trade name “SELLOGEN HR” from Henkle Corp.,Cincinnati, Ohio.

An exemplary ethoxylated tristyrylphenol phosphate potassium saltsurfactant is commercially available, for example, under the trade name“SOPROPHOR FLK” from Rhodia, Cranbury, N.J.

A nonionic surfactant is a surface-active molecule that does not containionizable polar end groups but does contain hydrophilic and lipophilicportions. Exemplary nonionic surfactants include polyoxyethylenealkylether or alkenylether surfactants. Nonionic surfactant used toprepare a suspension concentrate as described herein may include long orshort chain alcohol ethoxylate surfactant. The alcohol ethoxylatesurfactant may be branched or linear.

An example of a useful nonionic polyoxyalkylene surfactant includesalcohol ethoxylate having the general formula:R—O—((CH₂)_(x)O)_(y)—Hwherein R may be “long” or “short” chain and “branched” or “linear”alkyl. R preferably can be a “short chain” branched or linear alcohol,meaning that it can have from about 3 to 23 or fewer carbon atoms. Withrespect to the oxyalkylene, x can preferably be in the range from about2 to 5, preferably from about 2 to 4 (e.g., 2 or 3, for apolyoxyethylene or polyoxypropylene, respectively) and y can preferablybe in the in the range from 5 to 25.

Examples of useful short chain nonionic polyoxyalkylenes include linearalcohol polyoxyethylenes having the general formula:CH₃(C₂H₄)_(m)O(C₂H₄O)_(n)Hwherein CH₃(C₂H₄)_(m) is a short chain linear alkyl having from about 3to 23 or fewer carbon atoms (i.e., m can be in the range from about 1 to11 carbon atoms), and n is in the range from about 5 to 25.

Another example is short chain nonionic polyoxypropylenes having thegeneral formula:CH₃(C₂H₄)_(m)O(C₃H₆O)_(n)H,wherein CH₃(C₂H₄)_(m) is a short chain linear alkyl having from about 3to 23 or fewer carbon atoms (i.e., m can be in the range from about 1 to11 carbon atoms), and n can preferably be in the range from about 5 to25.

Exemplary short chain linear alcohol ethoxylate surfactant arecommercially available, for example, under the trade names “SURFONICL12-6” from Huntsman, Austin, Tex., “SURFONIC L24-7” from Huntsman,Austin, Tex., “TERGITOL 15-S-7”, “TERGITOL 24-L-60”, “ALPHONIC 1012-60”,“ALPOHONIC 1414-60”, “BIOSOFT ET 630,” from Stepan Company, Chicago,Ill., and “GENOPAL 24-L-60.”

Other exemplary surfactants include polyethylene glycol, fatty acidethoxylates, phosphate esters, octyl phenol ethoxylates, and nonylphenol ethoxylates.

Useful polyethylene glycol surfactants are commercially available, forexample, under the trade names “ADEKA PEG” from Asahi Denka Kogyo,Tokyo, Japan.

Useful fatty acid ethoxylate surfactants are commercially available, forexample, under the trade names “NINEX MT-610”, “NINEX MT-615”, and“NINEX MT-630” from Stepan, Northfield, Ill.

Useful phosphate ester surfactants are commercially available, forexample, under the trade names “STEPFAC 8180”, “STEPFAC 8181”, and“STEPFAC 8182” from Stepan.

Useful octyl phenol ethoxylate surfactants are commercially available,for example, under the trade name “MAKON OP-9” from Stepan, Northfield,Ill.

Useful nonyl phenol ethoxylate surfactants are commercially available,for example, under the trade names “MAKON 4”, “MAKON 6”, “MAKON 8”,“MAKON 10”, “MAKON 12”, and “MAKON 14” from Stepan, Northfield, Ill.

A cationic surfactant is a surface-active molecule in which an activeportion of a lipophilic portion of the molecule forms a positive ion(i.e., cation) when placed in aqueous solution. In one embodiment,exemplary cationic surfactant includes ethoxylated tallow amine.

Generally speaking, the amounts of surfactant and herbicide compound inan MFC can be any useful amounts, meaning that the amounts aresufficient to produce a useful herbicide composition or a usefulherbicide composition precursor, based on the amount of herbicidecompound dissolved in surfactant. Amounts of either organic solvent orwater may also be used to produce an MFC, but it is preferred that onlysmall amounts of organic solvent and more preferably no organic solventbe added to the MFC. Useful relative amounts of herbicide and surfactantwill vary for different herbicide compounds and different surfactants,as well as the optional presence of organic solvent or water. ExemplaryMFCs can include from about 10 to about 40 parts by weight, e.g., fromabout 20 to about 35 parts by weight herbicide compound in acid form,and from about 60 to about 90, e.g., from about 65 to about 80 parts byweight surfactant. Useful amounts of herbicide compound in acid form andsurfactant can of course be outside of these recited ranges, dependingon preference, and on factors such as the solubility of the herbicidecompound and whether an organic solvent or water is also present.

MFCs can be prepared by any methods useful to dissolve a herbicidecompound in acid form in a surfactant. In general, the herbicidecompound in acid form can typically be provided as a solid, but other,non-solid forms may also be available and useful, such as liquid oilsoluble acid herbicide compounds. An amount of the herbicide compound inacid form can be dissolved into a surfactant by selecting a propersurfactant or combination of surfactants (combinations of two or moresurfactants will be referred to collectively herein as “surfactant”),each in useful amounts. Heat can optionally be used to facilitatedissolution of herbicide compound in surfactant. For example a mixtureof herbicide compound and surfactant (with optional organic solvent) maybe heated at a temperature, e.g., in the range from about 100 F to about200 F, preferably from about 130 F to about 150 F, to facilitatedissolution of the herbicide compound in the surfactant. Organic solventor water may also be added to the mixture to facilitate dissolution,although it can be preferred to avoid the use of organic solvents.Agitation or other techniques may be used to encourage dissolution.

Other ingredients such as antifoaming agents may be included in the MFCor microemulsion, as necessary, and in amounts and using techniques thatwill be well understood. If an acidifying agent is added directly to aMFC or microemulsion, the acidifying agent can be added at any stage,e.g., by simple combining and mixing of acidifying agent and MFC ormicroemulsion.

The MFC can be diluted with water to produce a microemulsion. Relativeamounts of MFC and water used to prepare a microemulsion can be anyamounts that produce a useful microemulsion, and can depend on factorssuch as the composition of the MFC (e.g., the type and concentration ofthe herbicide compound), the intended application (including the plantto be controlled or the crop to be protected), the mode of application(e.g., field or aerial spraying or application from a hand-held sprayapplicator, or other technique), etc.

Although amounts outside of the following ranges can also be useful, andexact ratios can depend significantly on the identity of herbicidecompound used, exemplary MFCs can be combined with water to form amicroemulsion by mixing about 0.05 to about 7 parts by volume MFC withfrom about 93 to about 99.95 parts by volume water (e.g., 2 ml MFC to 98ml water, 1 quart MFC to 12 gallons water, 12 oz. MFC to 20 gallonswater, 0.065 parts MFC to 99.935 parts water, or equivalent amounts ordifferent of each). The actual amount of MFC to water can vary dependingon the herbicide compound, the crop or weed species, the amount of sprayvolume as chosen by the applicator, the desired strength of theapplication composition, whether other ingredients are added, etc. Thiscomposition may be applied as a herbicide application composition,optionally additionally including other ingredients such as a desiredamount of acidifying agent or one or more other herbicide compound orcomposition.

Another method of preparing a herbicide composition of the invention isfrom a suspension concentrate, especially a suspension concentratecompositions that includes glyphosate acid, i.e., glyphosate(N-(phosphonomethyl)glycine) in the acid form, or a suspensionconcentrate that contains an imidazolinone compound in acid form.

The glyphosate active herbicide compound (N-(phosphonomethyl)glycine)includes 4 acidic protons which are removed at pKa₁ of 0.8 (1^(st)phosphonic), pKa₂ 2.3 or 2.6 (carboxylate), pKa₃ 6.0 (2^(nd)phosphonic), and pKa₄ 11.0 (amine). For purposes of the presentdescription, when discussing the pKa of the glyphosate acid form of theN-(phosphonomethyl)glycine, the pKa₂ is specifically meant, because thisis the pKa that relates to the conversion of the glyphosate compound toand from the carboxylic acid form, which is generally considered to bethe “acid” form of the glyphosate herbicide compound. See, for example,http://www.soils.wisc.edu/virtual_museum/glyphosate/glyphosate_tx.html,which is part of the Virtual Museum of Minerals and Molecules,originally released 25 Dec., 1999, and last modified 31, Dec., 2000.

Glyphosate acid is commercially available, generally in the form of agranular, solid, powder form or as a wet cake, for example from DowChemical Co., under the trade name Glyphosate WC. These materials aresold in the form of solid glyphosate acid particles having an averagesize (diameter) in the range from about 5 to about 18 microns.

Glyphosate acid can be incorporated into a suspension concentrate, e.g.,as described in Assignees' copending U.S. patent application entitled“Herbicide Compositions Comprising Suspension Concentrate withGlyphosate Acid, Methods of Preparation, and Methods of Use,” filed onMar. 21, 2002, and having U.S. Ser. No.10/103,493. The term “suspensionconcentrate” as used herein, means a composition also sometimes referredto as an “aqueous flowable” or a “water-based flowable” composition,which compositions are known in the herbicide art and include or consistof particles of a generally insoluble solid active herbicide compound insuspension (preferably concentrated suspension) in water. The suspensionconcentrate can be produced with particles of glyphosate acid bysuspending and preferably dispersing the particles in water with theassistance of other ingredients such as conventional dispersants,surfactants (wetting agents), and other optional ingredients. Theglyphosate acid should be in the form of particles that exhibit physicalcharacteristics such as size, shape, etc., that will allow theglyphosate acid particles to be suspended in water as described. Theparticle size range can vary depending on factors such as the otheringredients used to prepare the suspension concentrate and theirrespective amounts, but exemplary particles may be in the size rangebelow about 10 microns, for example in the range from about 4 or 5 toabout 7 or 8 microns.

The suspension concentrate includes water in a useful amount, such as anamount that, in combination with one or more other ingredients describedherein (e.g., such as surfactant and/or dispersant) will allowsuspension and preferably dispersion of the glyphosate acid particles.Exemplary amounts of water in a suspension concentrate may be, forexample, in the range from about 20 to about 60 weight percent waterbased on the total weight of the suspension concentrate, such as fromabout 30 to about 50 weight percent water in a suspension concentrate.

A wetting agent, (also referred to herein as “surfactant”), can be usedto facilitate suspending the glyphosate acid particles in a suspensionconcentrate. A very large variety of surfactants are known andcommercially available, including such different classes as cationicsurfactants, anionic surfactants, non-ionic surfactants, ionicsurfactants, and amphoteric surfactants, etc. According to theinvention, the surfactant can be any surfactant or combination ofsurfactants useful to suspend particles of glyphosate acid. Examples ofsome preferred surfactants include cationic, non-ionic, and anionicsurfactants, either alone or in combinations (e.g., blends of cationicand nonionic surfactants). Of these, particular types of preferredsurfactants include non-ionic linear or branched alcohol ethoxylatesurfactants, anionic phosphoric acid ester surfactants (sometimesreferred to as “phosphate ester” surfactants), and cationic ethoxylatedtallow amine surfactants. An example of a useful type of surfactantincludes nonionic wetting agents, such as Surfonic L12-6, from Huntsman.

Examples of commercially available surfactants useful as wetting agentsor dispersants include those identified in the list of surfactants aboverelating to microemulsion-forming-concentrates and the following:GENERAL TRADE NAME COMMON NAME FUNCTION CLASSIFICATION Tomadol 1-5 11carbon 5 mole linear alcohol wetting agent nonionic Surfonic L12-6 12carbon 6 mole linear alcohol wetting agent nonionic Trymeen 6607 20 moletallow amine wetting agent/adjuvant cationic Stepfac 8170 phosphateester dispersant/adjuvant anionic Surfonic PE 1218 phosphate esterdispersant/adjuvant anionic Surfonic OP-70  7 mole octylphenol wettingagent/adjuvant nonionic Tergitol NP-9  9 mole nonylphenol wettingagent/adjuvant nonionic Soprophor 796P tristerol phenol EO/PO dispersantnonionic Soprophor FLK tristerolphenol potassium phosphate dispersantanionic Polyfon H sodium lignosulfonate dispersant anionic Morwet D425napthalene formaldehyde condensant dispersant anionic Morwet IPnaphthalene sulfonates wetting agent anionic Pluronic L1061 blockcopolymer dispersant nonionic Tersperse 4984 block copolymer/alcoholethoxylate dispersant, wetting nonionic Tersperse 2500 surfactantdispersant anionic Surfonic DOS60 sulfosuccinate wetting agent anionicLI-700 lecithin derivative adjuvant nonionic Goodrite K732 polyacrylicacid dispersant anionic

The amount of surfactant (“surfactant” refers to one or a combination ofsurfactants) can be any amount that will allow the preparation of asuspension concentrate. Useful amounts of surfactant or wetting agentwill be apparent to the skilled artisan based on this overalldescription, with exemplary amounts being below about 20 percent byweight surfactant or wetting agent based on the total weight of thesuspension concentrate, and with preferred amounts possibly being in therange from about 0.1 or 1 to about 10 or 15 weight percent surfactantbased on the total weight of the suspension concentrate, with the rangefrom about 0.5 to 3 weight percent being particularly preferred.

A dispersant can also be useful to facilitate preparation of asuspension concentrate containing glyphosate acid particles. An exampleof a useful type of dispersant would include nonionic dispersants, suchas Tersperse 4892, from Huntsman. The amount of dispersant can be anyamount that will allow the preparation of a suspension concentrate, andthat may help to stabilize a suspension concentrate, e.g., by preventingflocculation. Exemplary amounts of dispersant can be below about 10 or 8percent by weight dispersant based on the total weight of the suspensionconcentrate, with preferred amounts being from about 2 to about 6 weightpercent dispersant, based on the total weight of the suspensionconcentrate.

Other ingredients or additives can also be included in the suspensionconcentrate. For example, an antifreeze may be useful, such as propyleneglycol or other low molecular weight alcohols or polyols, in an amountto reduce the freezing point of the suspension concentrate, e.g., belowabout 20 weight percent based on the total weight of the suspensionconcentrate, for example from 1 to about 15 weight percent, or fromabout 5 to about 10 weight percent.

Thickeners can be included in the suspension concentrate in amountsuseful to provide gravitational stabilization by increasing viscosity.Useful thickeners include chemical compounds and polymeric materialsthat will be known to and understood by the skilled artisan, andinclude, generally, natural and synthetic starches, gums, and othertypes of chemical compounds that will increase the viscosity of asolution. Thickening agents are well known in the chemical and polymerarts, and include, inter alia, polyacrylamides, cellulosic resins andfunctionalized cellulosic resins, polyacrylic acids, polyethyleneoxides, and the like. Commercially available examples include Kelzan andRhodaopl xanthan gums, Attagel 50 and Attaflow FL clays, Carbopol 910polyacrylic acid polymer, Kelcosol sodium alginate, and Bentalitepurified Bentonite. Amounts of thickener below about 15 or 10 weightpercent based on the total weight of the suspension concentrate, maygenerally be useful. Preferred amounts may be less than 0.5 weightpercent for gums or cellulose resins.

Another ingredient in a suspension concentrate can include anantifoaming agent, with typical amounts being less than I percent byweight, e.g., less than 0.5 percent by weight.

Other useful additives to the suspension concentrate may include othersurfactants, antimicrobial agents, anticorrosion agents, and otheringredients that will be understood to be useful, in amounts that willalso be understood. Surfactants having functions of wetting, spreading,or penetrating, preferably to improve the efficacy of a herbicidecomposition, may also be added to a herbicide composition, e.g., as atank mix ingredient. Organic solvents may be included in the suspensionconcentrate if desired, but are generally not used or needed.

Ingredients of a suspension concentrate can be combined by know methods,including mixing, agitating, and dispersing, and, if needed or otherwisedesired, milling of the glyphosate acid particles, to produce thesuspension concentrate. Any of the mixing, milling, agitating,dispersing, or combining steps can be done in any order, such as millingthe glyphosate acid particles and adding the milled particles to waterand other ingredients, or by adding the particles to water and otheringredients followed by wet milling.

One exemplary method of producing a suspension concentrate starts withglyphosate acid particles in the form of a wet cake or dry (granular,powder) acid, generally having a relatively large particle size (e.g.,greater than about 10 microns). The wet cake or dry particles of thatsize can be mixed or dispersed into a liquid. This can be done, forexample, by combining the glyphosate acid particles with water and otheringredients with agitation or mixing to disperse the particles into thewater. For example, the glyphosate acid particles can be added to waterand one or more of surfactant, dispersant, antifreeze, and antifoam, andmixed using a high-speed mixer to disperse the glyphosate acidparticles. The mixture of glyphosate acid, water, and other ingredientscan be further processed toward a suspension concentrate by methods thatwill process the glyphosate acid particles into a form that allowssuspension of the particles in water in the form of a suspensionconcentrate, for instance by reducing the size of the particles in thepresence of a useful surfactant. Thus, a processing step can be toreduce the size of glyphosate acid particles to a size that will allowthe particles, in combination with one or more of the other ingredientsdescribed herein such as surfactant and/or dispersant, to be maintainedin a stable suspension concentrate composition. An exemplary method ofreducing the size of the glyphosate acid particles is by using millingtechniques, e.g., what is referred to as “wet milling.” Any method ofreducing particle size may be useful, such as by using an attritionmill, ball mill, sand mill, or other wet milling process.

After reduction of the particle size, the solution containing thesuspended glyphosate acid particles can be further combined with athickener, by mixing the thickener into the solution.

The herbicide compound in acid form can also be an imidazolinone acid,for example, as described in Applicants' U.S. Pat. No. 6,703,346entitled “Herbicide Compositions Comprising Imidazolinone Acid, Methodsof Preparation, and Methods of Use.” Imidazolinone compounds, andchemical derivatives thereof, are a known type of active herbicidecompound. Imidazolinone is generally available in either the acid orsalt form. The salt forms are considered to be generally soluble inwater, whereas the acid forms are considered to be generally insolublein water.

Imidazolinone in the acid form is considered to be generally aninsoluble active herbicide compound. This means, for example, dependingon temperature and pH, that imidazolinone acid can be soluble in wateror acidic water only up to a few weight percent, meaning thatapproximately 100 grams of an aqueous solution can dissolve onlyapproximately a couple of grams of imidazolinone acid, e.g.,approximately 1 gram, or one weight percent.

Examples of imidazolinone acids include imazethapyr acid, imazaquinacid, imazapyr acid, imazamethabenz acid, imazapic acid, imazamox acid,and combinations thereof. Imazethapyr acid has the molecular formulaC₁₅H₁₉N₃O₄ and is commercially available generally in the form of apowdered solid, under the trade designation “PURSUIT.” Imazaquin acidhas the molecular formula C₁₇H₁₇N₃O₃ and is commercially availablegenerally in the form of a powdered solid, under the trade designation“SCEPTER” and “IMAGE.” Imazapyr acid has the molecular formulaC₁₃H₁₅N₃O₃ and is commercially available generally in the form of apowdered solid, under the trade designation “ARSENAL,” “CHOPPER,” and“STALKER.” Imazamethabenz acid has the molecular formula C₁₅H₁₈N₂O₃ andis commercially available generally in the form of a powdered solid,under the trade designation “ASSERT.” Imazapic acid has the molecularformula C₁₄H₁₇N₃O₃ and is commercially available generally in the formof a powdered solid, under the trade designation “CADRE” and “PLATEAU.”Imazamox acid has the molecular formula C₁₅H₁₉N₃O₄ and is commerciallyavailable generally in the form of a powdered solid, under the tradedesignation “RAPTOR” and “ODESSEY.”

Exemplary imidazolinone acids described herein can generally have a pKabelow about 7, especially below about 5 or 4, for example, the pKa ofimazamethbenz is approximately 2.9, the pKa of imazapyr is approximately2 or 3, the pKa of imazaquin is approximately 3.8, and the pKa ofimazethapyr is approximately 3.9. Methods of determining pKa for aherbicide compound will be readily understood by the skilled artisan.

The use of imidazolinone acids can be advantageous because the acid formdoes not need to be converted to the imidazolinone salt form duringprocessing or prior to application, as is often done with imidazolinoneherbicide compounds, because the salt forms are more soluble in water.Instead, herbicide compositions that contain imidazolinone acid in theimidazolinone acid form, such as preferred suspension concentrates, canbe simple and economical to produce, and can be efficiently distributed,prepared, and applied without taking steps to convert the imidazolinoneherbicide out of its acid form. In addition, the acid form ofimidazolinone compounds, due to its uncharged state, can beadvantageously less affected or unaffected by hard water, e.g., lesssusceptible to de-activation by hard water.

In one preferred embodiment of the invention, a herbicide compositionincludes a suspension concentrate comprising imidazolinone acid. Thesuspension concentrates can be produced with particles of imidazolinoneacid compounds by suspending and preferably dispersing the particles inwater with the assistance of other ingredients such as surfactant (alsoreferred to as “wetting agents”), dispersant, and other optionalingredients.

The imidazolinone acid should be in the form of particles that exhibitphysical characteristics such as size, shape, surface features, etc.,that will allow the imidazolinone acid particles to be suspended in theform of a suspension concentrate, preferably an aqueous suspensionconcentrate. The particle size range can vary depending on factors suchas the other ingredients used to prepare the suspension concentrate andtheir respective amounts, but exemplary particles may be in the sizerange below about 10 microns, for example in the range from about 4 toabout 8 micrometers in diameter or from about 5 to about 7 micrometersin diameter.

Such herbicide compositions of the invention can include imidazolinoneacid in a useful amount. Useful amounts of imidazolinone acid in anyparticular composition can depend on factors such as the exactimidazolinone compound, the intended application (including the plant tobe controlled or the crop to be protected), the mode of application(e.g., field or aerial spraying or application from a hand-held sprayapplicator, or other technique), the method of any preparation of aherbicide application composition, the amounts and identities of otheringredients added to the herbicide composition, etc. For example, anamount that, in combination with one or more other ingredients describedherein (e.g., such as surfactant and/or dispersant) will allowsuspension and preferably dispersion of the imidazolinone acid particlesto provide a suspension concentrate. In one embodiment, useful amountsof imidazolinone acid compound in a suspension concentrate may be, forexample, in the range from about 20 to about 60 weight percentimidazolinone acid based on the total weight of the suspensionconcentrate. In another embodiment, useful amounts of imidazolinone acidcompound in a suspension concentrate may be, for example, in the rangefrom about 25 to about 45 weight percent imidazolinone and based on thetotal weight of the suspension concentrate. Exemplary concentrations ofsuspension concentrates prepared according to the invention can include3 pounds of imidazolinone acid per gallon, and 4 pounds of imidazolinoneacid per gallon. Other concentrations of imidazolinone acid will also beuseful.

Other ingredients may be used to prepare useful suspension concentratescontaining imidazolinone acids, as described above with respect toglyphosate acid suspension concentrates. Exemplary other ingredientsinclude surfactant, dispersant, thickener, and antifoaming agent.Similarly, methods as described as useful in preparing glyphosate acidsuspension concentrates can be useful in preparing suspensionconcentrates that contain imidazolinone acid herbicide compounds. Suchingredients and methods of preparing preferred suspension concentratescomprising imidazolinone acids, are described in Applicants' U.S. Pat.No. 6,703,346, entitled “Herbicide Compositions Comprising ImidazolinoneAcid, Methods of Preparation, and Methods of Use.”

Any form of the above described microemulsion-forming-concentrates,microemulsions, or suspension concentrates, or any other type ofherbicide composition, can be combined with an acidifying agent andapplied to plants for controlling plant growth with the herbicide beingpresent in the composition in the form of an acid compound, whenapplied. The acidifying agent may be incorporated into the herbicidecomposition at any convenient or useful time during preparation of aherbicide composition, e.g., acidifying agent may be added to aconcentrated or diluted form of a microemulsion-forming concentrate,microemulsion, suspension concentrate, or other form of herbicidecomposition containing a herbicide in acid form or containing aherbicide compound that will exist in the form of the acid compound oncethe compound is in the presence of acidifying agent.

Generally, as opposed to a precursor or a herbicide composition thatexists during processing, storage, or sale, a herbicide composition asused (i.e., applied to a plant) can be referred to as a “herbicideapplication composition.” The term “herbicide application composition”refers to a herbicide composition having a concentration of herbicidecompound that would normally be applied to a field or plant to controlundesired plant growth, as opposed, for example, to a composition havinga higher concentration of herbicide compound that may sometimes occur inpreparation, storage, shipping, or sale of a herbicide composition. Itis noted that any of the herbicide compositions described herein, suchas the MFC, microemulsion, or suspension concentrate, if inclusive of anacidifying agent, may be capable of controlling plant growth, e.g., ifapplied directly to a plant. Yet it is typical for reasons ofefficiency, cost, convenience, techniques presently used in applyingherbicide compositions, and environmental considerations, to use arelatively diluted form of herbicide composition to conveniently apply aspecific and known amount of herbicide compound per acre or per otherunit of application. By way of example, herbicide applicationcompositions include any herbicide composition having such a specificconcentration of herbicide compound for application, e.g., to a field,and may include microemulsions prepared directly by diluting an MFC withwater, microemulsions or other solutions prepared by diluting an MFCwith water and adding one or more other optional ingredient, andsuspension concentrates or diluted suspension concentrates, etc.

The amount and strength of acidifying agent can be taken into account indeciding the order of addition of ingredients and mode of preparation ofa herbicide composition. For instance, the acidifying agent may be addedto a precursor of the herbicide application composition, such as an MFC,a microemulsion, a suspension concentrate, a derivative of thesuspension concentrate, etc., or another type of herbicide formulation,at a time and in the manner that preferably does not have any unduenegative effect on either composition. An example of a method of makinga herbicide application composition would include tank mixing, meaning,for example, combining an MFC, microemulsion, or a suspensionconcentrate, with acidifying agent and optionally with water in a spraytank, preferably to produce a herbicide application composition having auseful concentration of herbicide compound in acid form, and alsopreferably having a pH below the pKa of the herbicide compound.

According to the invention, any amount of the acidifying agent can beincluded in the herbicide composition which will, for example, improvethe efficacy of the herbicide composition, and which can preferablyreduce the pH of the herbicide composition, most preferably to a pH thatis below the pKa of the herbicide compound. Examples of useful amountsof acidifying agents will be quite varied, considering a variety offactors mentioned in the present description. Relatively strongconcentrations of liquid (aqueous) acidifying agent solutions such as93% liquid sulfuric acid, 72% phosphoric acid, 85% polyphosphoric acid,90% nitric acid, 99% glacial acetic acid, etc., can be added directly orcan be first diluted and then added to a herbicide composition in anamount to bring the pH to below about 7, e.g., below about 5 or 6,preferably to below the pKa of the herbicide compound. In terms ofvolume percent, preferred amounts are highly dependent on the identityof the acidifying agent and the herbicide composition and its pKa. Verygenerally speaking, useful amounts of acidifying agent in a herbicideapplication composition can be below about 5 or 10 volume percent, e.g.,in the range from about 0.01 to about 4 volume percent, or parts byvolume acidifying agent per 100 parts by volume of herbicide applicationcomposition. Of course amounts of acidifying agent outside of theseranges can also be useful, and an amount used will depend in great parton the type and strength (e.g., concentration) of the particularacidifying agent chosen, as well as the desired pH of the herbicidecomposition.

Herbicide compositions of the invention can be used for immediate andlong-term, pre- and post-emergent control of a large variety ofdifferent forms of vegetation, particularly upon appropriate selectionof the herbicide compound. As an example, a herbicide composition in aconcentrated form, e.g., a microemulsion-forming-concentrate,microemulsion, or a suspension concentrate, with a desired amount ofacidifying agent, may be applied directly to a plant for controllingplant growth. More typically, a herbicide concentrate such as asuspension concentrate or a microemulsion-forming-concentrate, or even amicroemulsion, could be sold as a herbicide concentrate product. Such aconcentrate that includes an acidifying agent, could be diluted withwater, such as by tank mixing, and then applied. Alternatively, aherbicide concentrate composition could be sold and purchased in a formthat does not include an acidifying agent. This composition could becombined with an acidifying agent (e.g., by tank mixing), optionallydiluted, and then applied. A herbicide concentrate composition that doesnot contain acidifying agent could be purchased by distributors orsuppliers, or directly by consumers, either one of which could addacidifying agent and optionally water, or another type of herbicide orherbicide compound.

In one embodiment of a distribution system, a herbicide concentratecomposition could be sold to farming product or nursery dealers, or thelike, who could dilute the concentrate composition with water and/or addan acidifying agent. This could be particularly convenient if such adealer normally kept on hand a stock of acidifying agent such asphosphoric acid or sulfuric acid, etc. The concentrate composition,combined with an acidifying agent by the dealer, could be sold to an endconsumer, who could use the herbicide composition as purchased or whocould optionally further dilute the purchased herbicide composition oradd other ingredients to the purchased herbicide composition such as anadditional herbicide by tank mixing.

The herbicide compositions of the invention can be applied for immediatevegetation control by contact killing, by application of a herbicidecomposition to plants. Herbicide application compositions can contain auseful amount of herbicide compound, based on factors of efficacy andsafety, etc. Similarly, the amount of herbicide application compositionapplied to a plant or a field will be readily understood by those ofskill, based, e.g., on desired efficacy, dosage, safety, andenvironmental factors.

The particular amount of herbicide compound in any specific herbicideapplication composition will depend on factors as known and describedabove, and in particular on the identity of the specific herbicidecompound. Advantageously, it has been found that certain preferredherbicide application compositions of the invention, in particular thosethat have a pH below the pKa of the herbicide compound, can be appliedat lower dosages (lower amounts of herbicide compound per plant or peracre) relative to other herbicide compositions containing the sameherbicide compound, but not in the acid form or not at a pH below thepKa of the herbicide compound.

Examples of dosages of herbicide compound according to the invention,especially herbicide compositions of the described pH, can be in therange from about 1/100 or 1/10 to about 10 pounds herbicide compound peracre, with dosages in the range from about 1/100 or 1/10 to about 6pounds herbicide compound per acre being sometimes preferred, e.g., fromabout 0.03 to 0.5 or 1 pound per acre. More resistant plants may requirehigher concentrations and/or higher dosage rates. The preparation ofherbicide application compositions suitable to apply useful dosagesbased on the concentration of herbicide compound in a microemulsion,MFC, suspension concentrate, etc., will be well understood by those ofordinary skill.

The herbicide compositions can be applied using conventional aerial andfield spray techniques in field applications. The herbicide compositionscan also be applied by any other useful technique, such as byspot-application to undesired plant growth using a hand-held applicator,or the like.

Advantageously, certain herbicide compositions of the invention havebeen found to exhibit the additional advantage of being relativelynon-volatile. The advantage of non-volatile herbicide compositions areself-evident to those of skill in the herbicide arts. A non-volatileherbicide composition has the advantage of not evolving, or evolving toa reduced degree, through the air, to inadvertently contact desiredplant growth. In practical effect, this advantageous property allows theherbicide compositions of the invention to be applied to undesired plantgrowth in greater strength or in closer proximity to desiredabove-ground plant growth.

The herbicide compositions can be used for both immediate and long-termcontrol of a large variety of vegetation including those usually foundin agricultural fields such as bushes, scrub brush, vines, and otherweeds.

Illustrative of vegetation that can be controlled by these methods,depending significantly on the identity of the active herbicidecompound, are: black mustard (brassica nigra), curly dock (rumexcrispus), common groundsel (senecio vulgaris), pineapple weed(matricaria matricarioides), swamp smartweed (kelp) (polygonumcoccineum), prickly lettus (lactuca scariola), lance-leaved groundcherry(physalis lanceifolia), annual sowthistle (sonchus oleraceus), londonrocket (sisymbrium irio), common fiddleneck (amsinckia intermedia),hairy nightshade (solanum sarrachoides), shepherd's purse (capsellabursa-pastoris), sunflower (helianthus annus), common knotweed(polygonum aviculare), green amaranth (amaranthus hybridus), mare's tail(conyza canadensis), henbit (lamium amplexicaule), cocklebur (xanthiumstrumarium), cheeseweed (malva parviflora), lambsquarters (chenopodiumalbum), puncture vine (tribulus terrestris) common purslane (portulacaoleracea), prostrate spurge (euphorbia supina), telegraph plant(heterotheca grandiflora), carpetweed (mollugo verticillata), yellowstarthistle (centaurea solstitialis), milk thistle (silybum marianum),mayweed (anthemis cotula), burning nettle (urtica urens), fathen(atriplex patula), chickweed (stellaria media), scarlet pimpernel(anagallis arvensis) redroot pigweed (amaranthus retroflexus),minnerslettuce (montia perfoliata), turkey mullein (eremocarpussetigerus), nettleleaf goosefoot (chenopodium murale), prostrate pigweed(amaranthus blitoides), silverleaf nightshade (solanum elaeagnifolium),hoary cress (cardaria draba), largeseed dodder (cuscuta indecora),California burclover (medicago polymorpha), horse purslane (trianthemaportulacastrum), field bindweed (Iconvolvulus arvensis), Russianknapweed (centaurea repens), flax-leaved fleabane (conyza bonariensis),wild radish (raphanus sativus), tumble pigweed (amaranthus albus),stephanomeria (stephanomeria exigua), wild turnip (brassica campestris),buffalo goard (cucurbita foetidissima), common mullein (verbascumthapsus), dandelion (taraxacum officinale), Spanish thistle (xanthiumspinosum), chicory (cichorium intybus), sweet anise (foeniculumvulgare), annual yellow sweetclover (melilotus indica), poison hemlock(conium maculatum), broadleaf filaree (erodium botrys), whitestemfilaree (erodium moschatum), redstem filaree (erodium cicutarium),ivyleaf morning-glory (ipomea hederacea), shortpod mustard (brassicageniculata), buckhorn plantain (plantago lacenolata), sticky chickweed(cerastium viscosum), himalaya blackberry (rubus procerus), purslanespeedwell (veronica peregrina), Mexican tea (chenopodium ambrosioides),Spanish clover (lotus purshianus), Australian brassbuttons (cotulaaustralis), goldenrod (solidago californica), citron (citrulluslanatus), hedge mustard (sisymbrium orientale), black nightshade(solanum nodiflorum), Chinese thornapple (datura ferox), bristly oxtongue (picris echioides), bull thistle (cirsium vulgare), spinysowthistle (sonchus asper), Tasmanian goosefoot (chenopodium pumilio),goosefoot (chenopodium botrys), wright groundcherry (physalisacutifolia), tomatillo groundcherry (physalis philadelphica), prettyspurge (euphorbia peplus), bitter apple (cucumis myriocarpus), indiantobacco (nicotiana bigelovii), common morning-glory (ipomoea purpurea),waterplantain (alisma triviale), smartweed (polygonum lapathifolium),mature sowthistle (sonchus asper), yellow nutsedge (cyperus esculentus),purple nutsedge (cyperus rotundus), lupine (lupinus formosus), andgrasses of the family Gramineae such as annual rye grass, blue grass,water grass, barnyard grass, bermuda grass, fescue, mat grass, Johnsongrass, and the like.

The ingredients of a herbicide composition, e.g., one or more of theherbicide compound, surfactant, acidifying agent, etc., can be selectedin view of the type of control desired (i.e., pre-emergent orpost-emergent) and the type of vegetation to be controlled according tothe known attributes of the herbicide compound.

As mentioned, other herbicides or herbicide compositions can optionallybe added to herbicide compositions of the invention, to provide broadrange protection against certain varieties of plants. As a singleexample, glyphosate acid (N-phosphonomethylglycine acid) can be usefulin combination with other herbicide compounds in the herbicidecompositions of the invention. Glyphosate acid can be included in aherbicide composition in any useful amount, especially in a herbicideapplication composition in an amount of glyphosate acid that willprovide complementary protection to another herbicide compound of theherbicide composition. Imidazolinone acid herbicide compounds can alsobe used in combination with other active herbicide compounds. See, e.g.,Applicants' copending patent application entitled “Herbicide CompoundsComprising Suspension Concentrate with Glyphosate Acid, Methods ofPreparation, and Methods of Use,” having U.S. Ser. No. 10/103,493; andApplicants' U.S. Pat. No. 6,703,346, entitled “Herbicide CompositionsComprising Imidazolinone Acid, Methods of Preparation, and Methods ofUse,” incorporated herein by reference. Also, the pH of such a herbicidecomposition can preferably be below the pH of glyphosate acid orimidazolinone acid, as relevant, e.g., below about 2.6, so theglyphosate or imidazolinone can exist in the acid form, preferablyimproving efficacy and avoiding precipitation.

EXAMPLES

Below are described specific microemulsion-forming-concentrates of acidherbicides in surfactants, diluted to form microemulsions (all amountsin weight percent). 2,4D Acid ME Attempt to make 33.3%/wt 2,4-D. Formedan initial clear MFC which was diluted to 2% in water to form amicroemulsion. Formulation crystallized in 24 hours. Tomadol 1-5 32.2%Tomadol 1-7 32.8 Rhodafac RS 710 1.0 98% 2,4D Acid 34.0 2% dilution (2parts MFC to 98 parts water) in 342 ppm is clear microemulsion, 4 hrs.2,4D Acid ME Tomadol 1-5 36.1% Tomadol 1-7 36.1 98% 2,4D Acid 27.8 2%dilution in 342 ppm is clear microemulsion, 4 hrs. Fluroxypyr acid &2,4-D Acid ME Tomadol 1-5 13.9% Tomadol 1-7 13.9 SAG 10 AF 0.1 Trymeen6607 50.0 Cognis tallow amine ethoxylate 99% Fluroxypyr Acid 11.0 98%2,4D Acid 11.1 2% dilution in 342 ppm opaque microemulsion @ 4 hrs 2,4DAcid ME Surfonic L12-6 71.3% Huntsman 12 carbon 6 mole linear alcoholSAG 10 AF 0.1 98% 2,4D Acid 28.6 5% dilution in 342 ppm is opaquemicroemulsion 2,4D Acid ME Tomadol 1-5 63.2% Stepfac 8170 8.0 StepanPhosphoric acid ester SAG 10 AF 0.1 98% 2,4D Acid 28.6 5% dilution in342 ppm is opaque microemulsion 2,4D Acid ME Surfonic L12-6 63.3%Surfonic PE-1218 8.0 Huntsman Phosphoric acid ester SAG 10 AF 0.1 98%2,4D Acid 28.6 5% dilution in 342 ppm is opaque microemulsion 2,4D AcidME Surfonic L12-6 61.3% Huntsman linear alcohol Surfonic PE-1218 10.0Huntsman Phosphoric acid ester SAG 10 AF 0.1 98% 2,4D Acid 28.6 2%dilution in 342 ppm is opaque microemulsion 2,4D Acid ME Surfonic DDA661.3% Huntsman branched alcohol ethoxylate Surfonic PE-1218 10.0Huntsman Phosphoric acid ester SAG 10 AF 0.1 98% 2,4D Acid 28.6 2%dilution in 342 ppm is opaque microemulsion 2,4D Acid ME Surfonic TDA663.3% Huntsman tridecyl alcohol ethoxylate Surfonic PE-1218 8.0 HuntsmanPhosphoric acid ester SAG 10 AF 0.1 98% 2,4D Acid 28.6 2% dilution in342 ppm is opaque microemulsion 2,4D Acid ME Tomadol 1-5 32.0 Tomahlinear alcohol ethoxylates Tomadol 1-7 31.30 Stepfac 8170 8.00 StepanPhosphoric acid ester SAG 10 AF 0.1 98% 2,4D Acid 28.6 5% dilution in342 ppm is opaque microemulsion 2,4D Acid ME Tomadol 1-5 32.0 Tomahlinear alcohol ethoxylates Tomadol 1-7 31.30 Stepfac 8170 8.00 StepanPhosphoric acid ester SAG 10 AF 0.1 98% 2,4D Acid 28.6 2% dilution in342 ppm is opaque microemulsion Fluazifop Acid ME Surfonic L12-6 63.3%Stepfac 8170 8.00 Stepan Phosphoric acid ester SAG 10 AF 0.10 90%Fluzafop Acid 28.60 Fluroxypyr Acid ME, using organic solvent SurfonicL12-6 24%/wt linear alcohol nonionic Surfonic T-15 45 tallow aminecationic THFA # 10 solvent 99% fluroxypyr acid 21 active #tetrahydrofurfuryl alcohol 2,4D Acid ME Surfonic OP-70 63.3% 7 moleoctyl phenol Stepfac 8170 8.0 98% Dow 2,4D Acid 28.6 SAG 10 Antifoam 0.12,4D Acid ME Tergitol NP6 63.3% 6 mole nonyl phenol Stepfac 8170 8.0 98%Dow 2,4D Acid 28.6 SAG 10 Antifoam 0.1 2,4D Acid ME Trylox 5902 63.3% 16mole castor oil ethoxylate Stepfac 8170 8.0 98% Dow 2,4D Acid 28.6 SAG10 Antifoam 0.1 2,4D Acid ME Span 20 35.3% sorbitan laurate Tween 8028.0 polysorbate 80 Stepfac 8170 8.0 98% Dow 2,4D Acid 28.6 SAG 10Antifoam 0.1 2,4D Acid ME Sophroflor 796P 68.3% ethoxylatedtristerylphenol Stepfac 8170 8.0 98% Dow 2,4D Acid 28.6 SAG 10 Antifoam0.1 ME with Glyphosate Acid & 2,4D Acid Dipropylene glycol mono methylester 5.00% 40 mole castor oil ethoxylate 10.00 98% 2,4D acid 6.20 97%glyphosate acid 6.20 Amads 72.50 Antifoam 0.10Microemulsions were Formed as Follows:

Microemulsion-forming-concentrate was formed by adding dicamba tosurfactant and mixing until dissolved with heat. Then, Engame andantifoam were mixed and added to the dicamba/surfactant MFC to form amicroemulsion: Neodol 1-5 20.00% linear alcohol ethoxylate 88% dicambaacid 6.60 Engame 73.30 Antifoam 0.10(Engame is 9.6% glyphosate acid dissolved in a urea-sulfuric acid waterbase.)

In a method of using a composition containing herbicide acid (thecombination of glyphosate acid and 2,4-D acid), surfactant, andacidifying agent, glyphosate acid was dissolved in surfactant andingredients to produce a sulfuric acid/urea adduct, and that mixture wasthen used to solubilize 2,4-D in surfactant. A. Vessel - Add in orderlisted keeping temperature below 130° F. Water 13.17% 93% sulfuric acid35.30 97% glyphosate acid 6.80 Urea 20.30 Copper sulfate 0.02 corrosioninhibitor Antifoam 0.01 B. Vessel - Add in order listed keepingtemperature between 130-150° F. Tomadol 1-5 8.00 11 carbon 5 mole linearalcohol ethoxylate Tomadol 1-7 8.00 11 carbon 7 mole linear alcoholethoxylate Rhodofac RS 710 1.70 anionic, phosphate ester surfactant 98%2,4D Acid 6.70

The samples were clear. The solution of Vessel B was a microemulsion.Adding the solution of Vessel A to the solution of Vessel B withagitation formed a clear MFC product which when diluted, 2 parts MFCproduct to 98 parts water, formed an opaque microemulsion.

A suspension concentrate comprising 3 lbs. glyphosate acid per galloncan be prepared as described above, with ingredients as follows: Water41.60% SAG 30 Antifoam 0.30 Propylene Glycol 5.00 Surfonic T-15 8.00tallow amine 15 mole 86% glyphosate wc 36.10 wet cake Tersperse 49842.00 dispersant, wetter 2% Kelzan 0.5% Proxel 7.00

Other exemplary suspension concentrate formulations can include a higheramount of surfactant (e.g., 8%) and can have a glyphosate acidconcentration of 4 pounds per gallon, as follows: Water 32.45% SAG 300.30 antifoam Propylene Glycol 8.00 antifreeze AU-392 8.00nonionic/tallow amine blend Glyphosate WC, Dow 45.30 active, 39.0%glyphosate acid Tersperse 4894 2.00 dispersant, wetter 2% Kelzan-0.5%Proxel 4.00 thickener & antimicrobial Total 100.00

Water 32.45% SAG 30 0.30 antifoam Propylene Glycol 8.00 antifreezeLI-700 8.00 lecithin derivative Glyphosate WC, Dow 45.30 active, 39.0%glyphosate acid Tersperse 2500 2.00 dispersant 2% Kelzan-0.5% Proxel4.00 thickener & antimicrobial Total 100.00

Examples 1-5

Materials and Methods:

Five experiments were conducted to evaluate the efficacy of a variety ofdifferent types of herbicide formulations, including formulations fromsuspension concentrates, and to evaluate the effect of adding acids tothe spray solution as an adjuvant (see Tables 1-5). Each treatment inthe experiment was replicated three times. An untreated control was alsoincluded in each experiment.

Experiment one was designed to identify useful acid concentrations offour acids when used with a 2,4-D acid (2,4-dichlorophenoxy acetic acid)formulation (PCC-1133), or a glyphosate (N-(phosphonomethyl)glycine)acid formulation (PCC-1168 suspension concentrate containing glyphosateacid), in a greenhouse. These treatments were compared to standard 2,4-Dand glyphosate formulations (ROUNDUP ULTRA, SABER, SALVO), and anuntreated control.

Experiment two determined the effect of adding four different acidadjuvants to five formulations of glyphosate: RODEO, ROUNDUP, ROUNDUPULTRA, ENGAME, and PCC-l 168, at four different glyphosate rates. (TheKochia for experiment 2 did not germinate well.)

Experiment three considered the effect of adding acid adjuvants toPCC-1133, and compared the results to SALVO, SABER, and PCC-1133.Experiment four determined the effect of a variety of acid adjuvants:sulfuric acid, hydrochloric acid, nitric acid, glacial acetic acid,phosphoric acid, perchloric acid, perchloric acid, and polyphosphoricacid, on the efficacy of the 2,4-D acid formulation, PCC-1133, and theacid formulation alone, compared to ester and amine formulations of2,4-D.

Experiment four determined the effect of a variety of acid adjuvants:sulfuric acid, hydrochloric acid, nitric acid, glacial acetic acid,phosphoric acid, perchloric acid, perchloric acid, and polyphosphoricacid, on the efficacy of the 2,4-D acid formulation, PCC-1133.

Experiment five determined the effect of the same acid adjuvants on theefficacy of the glyphosate acid formulation, PCC-1168, compared toanother glyphosate formulation, Rodeo. PCC-1168 Suspension ConcentrateFormulation % AI- INGREDIENT Tech %/WT Water 44.60 SAG 30, OSI, Antifoam0.30 Proplyene Glycol, Antifreeze 8.00 Surfonic L12-6, Huntsman,nonionic wetting agent 0.50 Glyphosate WC, Dow, Active Ingredient 86.0036.10 Tersperse 4894, Huntsman, nonionic dispersant 3.50 Gum 2%Kelzan-0.5% Proxel Premix*, thickener & 7.00 antimicrobial (* Delivers0.14% Kelzan, 0.03% Proxel) Add in order listed to cowles high speedmixer stopping prior to Kelzan-Proxel addition Grind to 5-18 microns, 4hrs in attritor, 60% Let down to mix tank with scales TOTAL 100.00 Addcalculated amount Kelzan/Proxel Premix** Add to milled liquid. Blendmoderately for 30 min. PCC-1133 Microemulsion Formulation 2,4-D Acid28.0 98% 2,4-D acid technical flake Tomadol 1-5 32.0 11 carbon 5 molelinear alcohol ethoxylate Tomadol 1-7 32.3 11 carbon 7 mole linearalcohol ethoxylate Rhodofac RS 710 8.0 anionic, phosphate estersurfactant SAG 10 Antifoam 0.1

The PCC-1133 microemulsion was prepared by adding surfactants to amixing vessel and warming to 130 F-150 F. Antifoam and acid were addedand mixed in until clear, with the 2,4-D acid becoming dissolved in thesurfactant, producing a MFC. A microemulsion was formed from the MFC bycombining 2 ml of the MFC with 98 ml water with agitation.

Procedure

For each experiment conducted, greenhouse flats 26 cm2 by 6 cm deep werefilled with Metro Mix 200 potting soil (experiments one and two) orMetro Mix 350 (experiments three, four, and five). The soil waspre-wetted before filling the flats. Six furrows were pressed into thesoil in each flat using a custom designed form. Corn, tame oats, wheat,pinto beans, cotton, and sunflower were planted in each tray. Cottonseedwas soaked for three days previous to planting to improve germination.However, germination was still unacceptable and kochia was substitutedin experiments two through five. One species was planted in each of thesix rows in each flat. Five seeds were planted in each row of corn,bean, and cotton, and sunflower. Six seeds were planted in each row ofoat and wheat. Kochia was sprinkled evenly along the row by hand. Eachflat was covered with 2 cm of soil and placed in the greenhouse.Greenhouse conditions were 28/20 C day/night temperatures and 16/8 h daynight periods. Light was supplemented with 400 W sodium halide lights.

The plants were allowed to germinate and grow in the greenhouse for 2weeks and then treated. Treatments were mixed using serial dilutions. Inexperiment one, the percent acid was reduced in each dilution by onehalf. In experiments 2 through 5 each dilution reduced the herbiciderate by one half. Acid concentrations were calculated and mixed so thata treatment with one of the acids or LI-136 would have the same amountof acid as the treatment with PCC-1174 (see infra). Therefore, atreatment designated 4% sulfuric acid would have the same amount of acidas a treatment with 4% PCC-1174.

After mixing in experiments one, four, and five, the pH of the spraysolution of each treatment was measured with a, VWR Scientific model8005 pH meter. The pH was measured to determine if the acid used or theamount of acid added was sufficient to lower the pH below the pKa of theacid herbicides used. The pKa of 2,4-D acid in the PCC-1133 is 2.87. ThepKa of glyphosate acid in PCC-1168 is about 2.5 or 2.6.

At the time of treatment, crops were at the following stages: corn—2 to3 If, oat—2 to 3 If, cotton—cotyledon, kochia—7 If, bean—1st trifoliate,and sunflower—2 to 4 If. Plants were treated using a greenhouse tracksprayer equipped with an 8001E nozzle and calibrated to deliver 140 Lha-1 at the height of the crop canopy. Each treatment was simultaneouslyapplied to three trays of plants, one for each replicate. Aftertreatment, the plants were left in the head house to dry and thentransferred to the greenhouse. Plants in each treatment were evaluatedvisually for injury 1 day, 1 week, and 2 weeks after treatment. SUMMARYOF VARIABLES OF EXPERIMENTS 1-5 Acid of each Acid Volume HerbicideTreatment v/v % Herbicide Rate lb/A Plants Reps Experiment 1 PCC-1174 0PCC-1133 0.125 dry beans 3 Sulfuric 0.125 PCC-1168 0.125 wheat 2 ofstandards Phosphoric 0.5 Roundup 0.125 cotton 2 of PCC- Ultra 1133 and1168 alone LI-136 1 Saber 0.125 corn =192 flats 2 Salvo 0.125 sunflower4 Untreated 0.125 oats Treatment Rates lb/A Plants Reps Experiment 2Rodeo 0.0313 dry beans 3 Roundup 0.0625 wheat Ultra 0.125 kochia (didnot germinate) Engame 0.25 corn PCC-1168 sunflower PCC-1168 + PCC-1174(4%) oats PCC-1168 + sulfuric (2%) PCC-1168 + phosphoric (2%) PCC-1168 +LI-136 (2%) Experiment 3 SALVO 0.0313 dry beans 3 SABER 0.0625 wheatPCC-1133 0.125 kochia PCC-1133 + PCC-1174 (2%) 0.025 corn PCC-1133 +Sulfuric (2%) 0.5 sunflower PCC-1133 + Phosphoric (2%) oats PCC-1133 +LI-136 (2%) Experiment 4 PCC-1133 0.0313 dry beans 3 PCC-1133 + Sulfuric(2%) 0.0625 wheat PCC-1133 + HCl (2%) 0.125 kochia PCC-1133 + Nitric(2%) 0.025 corn PCC-1133 + Acetic (2%) 0.5 sunflower PCC-1133 +Phosphoric (2%) oats PCC-1133 + Perchloric (2%) PCC-1133 +Polyphosphoric (2%) Experiment 5 PCC-1168 0.0313 dry beans 3 PCC-1168 +Sulfuric (4%) 0.0625 wheat PCC-1168 + HCl (4%) 0.125 kochia PCC-1168 +Nitric (4%) 0.025 corn PCC-1168 + Acetic (4%) 0.5 sunflower PCC-1168 +Phosphoric (4%) oats PCC-1168 + Perchloric (4%) PCC-1168 +Polyphosphoric (4%)

Following are data that illustrate the efficacy of various herbicidecompositions of Experiments 2-5. The injury caused by the herbicidetreatment was rated visually. Plants were observed and compared to theuntreated control. All the plants of each species in each replicationwere given a single rating. A rating of 0=no injury—the plants look thesame as the untreated. A rating of 100=dead—usually highly necrotic,brown and no chance of producing seed.

SALVO® is a commercially available product of Platte Chemical Co.containing 5 lb 2,4-D acid equivalent/gallon as 2-ethyl-hexyl ester of2,4-D SABER® is 2,4-D formulated as a dimethylamine salt(2,4-dichlorophenoxy dimethylamine salt), i.e., is a commerciallyavailable product of Platte Chemical Company containing 3.8 lb 2,4-Dacid equivalent/gallon as dimethylamine salt.

RODEO is a soluble liquid water-based formulation of IPA, glyphosate,and water, commercially available from MONSANTO, and was used accordingto the labeling instructions.

RODEO ULTRA is a glyphosate salt herbicide composition commerciallyavailable from MONSANTO, and was used according to the labelinginstructions.

ENGAME is a soluble liquid water-based formulation of glyphosate acid,urea, sulfuric acid, and water, commercially available from ENTEK, andwas used according to the labeling instructions.

ROUNDUP and ROUNDUP ULTRA are commercially available IPA glyphosate saltand surfactant herbicide compositions. Acidifying Agents HCI 37% Nitric70% Glacial Acetic 100% Perchloric 60% Polyphosphoric 100% PCC-1174Commercially available as “AMADS,”which is urea and H₂SO₄ in water:Chemical Name 1-amino methanamide dihydrogen tetraoxosulfate, orsulfuric acid and urea Molecular Formula NH₂C(OH)NHSO₄H₂

INGREDIENT %/WT Water 22.99 93% Sulfuric Acid 48.65 99% Urea 26.64Stepfac 8170 1.71 SAG 10 Antifoam 0.01LI-136 = LI-136 is a blend of 50 wt. % 21-0-0 urea liquor and 50 wtpercent of 72% phosphoric acid in water.The phrase “21-0-0 urea liquor” means a liquid that contains 21% byvolume urea (nitrogen), 0% by volume phosphate (phosphorus), and 0% byvolume potash (potassium).

Each of these acids were used as is and combined with the PCC-1133 orPCC-1168 to form a solution that contains 2 percent or 4 percent byvolume of the acid solution, as indicated in the data tables, and suchthat the pH of the herbicide composition was below the pKa of theparticular herbicide compound.

The ingredients of the herbicide compositions as applied are listed inthe following data tables for Experiments 2-5, and were diluted withwater and used at the rates indicated for herbicide ingredients andacidifying agents. DATA FOR EXPERIMENT 2 (TWO WEEK) Rate Units corn tameoat spring wheat dry bean sunflower 1 RODEO .0313 LB AE/A 0.0 0.0 0.00.0 0.0 2 RODEO .0625 LB AE/A 0.0 0.0 0.0 5.0 5.0 3 RODEO 0.125 LB AE/A20.0 20.0 0.0 30.0 40.0 4 RODEO 0.25 LB AE/A 30.0 10.0 40.0 60.0 100.0 5ROUNDUP .0313 LB AE/A 0.0 0.0 0.0 0.0 0.0 6 ROUNDUP .0625 LB AE/A 20.05.0 0.0 33.3 40.0 7 ROUNDUP 0.125 LB AE/A 70.0 70.0 60.0 50.0 90.0 8ROUNDUP 0.25 LB AE/A 90.0 80.0 70.0 80.0 100.0 9 ROUNDUP ULTRA .0313 LBAE/A 20.0 0.0 0.0 0.0 0.0 10 ROUNDUP ULTRA .0625 LB AE/A 30.0 20.0 40.050.0 40.0 11 ROUNDUP ULTRA 0.125 LB AE/A 90.0 49.0 70.0 70.0 90.0 12ROUNDUP ULTRA 0.25 LB AE/A 100.0 80.0 90.0 80.0 100.0 13 ENGAME .0313 LBAE/A 20.0 0.0 0.0 60.0 60.0 14 ENGAME .0625 LB AE/A 40.0 20.0 20.0 60.063.3 15 ENGAME 0.125 LB AE/A 50.0 40.0 30.0 60.0 90.0 16 ENGAME 0.25 LBAE/A 90.0 80.0 90.0 75.0 100.0 17 PCC-1168 .0313 LB AE/A 0.0 0.0 0.0 0.00.0 18 PCC-1168 .0625 LB AE/A 0.0 0.0 0.0 0.0 0.0 19 PCC-1168 0.125 LBAE/A 20.0 50.0 10.0 20.0 16.7 20 PCC-1168 0.25 LB AE/A 70.0 60.0 80.046.7 40.0 21 PCC-1168 .0313 LB AE/A 50.0 30.0 5.0 40.0 40.0 PCC-1174 4 %V/V 22 PCC-1168 .0625 LB AE/A 50.0 60.0 20.0 40.0 40.0 PCC-1174 4 % V/V23 PCC-1168 0.125 LB AE/A 70.0 60.0 70.0 63.3 76.7 PCC-1174 4 % V/V 24PCC-1168 0.25 LB AE/A 90.0 80.0 80.0 80.0 100.0 PCC-1174 4 % V/V 25PCC-1168 .0313 LB AE/A 10.0 10.0 10.0 40.0 5.0 SULFURIC ACID 2 % V/V 26PCC-1168 .0625 LB AE/A 10.0 10.0 10.0 40.0 10.0 SULFURIC ACID 2 % V/V 27PCC-1168 0.125 LB AE/A 50.0 20.0 10.0 60.0 28.0 SULFURIC ACID 2 % V/V 28PCC-1168 0.25 LB AE/A 90.0 70.0 80.0 80.0 90.0 SULFURIC ACID 2 % V/V 29PCC-1168 .0313 LB AE/A 0.0 0.0 0.0 0.0 1.7 PHOSPHORIC ACID 4 % V/V 30PCC-1168 .0625 LB AE/A 0.0 0.0 0.0 20.0 5.0 PHOSPHORIC ACID 4 % V/V 31PCC-1168 0.125 LB AE/A 5.0 5.0 5.0 40.0 40.0 PHOSPHORIC ACID 4 % V/V 32PCC-1168 0.25 LB AE/A 60.0 60.0 40.0 60.0 80.0 PHOSPHORIC ACID 4 % V/V33 PCC-1168 .0313 LB AE/A 5.0 0.0 0.0 10.0 20.0 LI-136 4 % V/V 34PCC-1168 .0625 LB AE/A 5.0 0.0 0.0 20.0 40.0 LI-136 4 % V/V 35 PCC-11680.125 LB AE/A 20.0 0.0 10.0 40.0 70.0 LI-136 4 % V/V 36 PCC-1168 0.25 LBAE/A 50.0 50.0 60.0 70.0 100.0 LI-136 4 % V/V 37 UNTREATED 0.0 0.0 0.00.0 0.0 DATA FOR EXPERIMENT 3 (TWO WEEK) tame Rate Units corn oat kochiawinter wheat dry bean sunflower 1 SALVO .0313 LB AE/A 0.0 0.0 0.0 0.010.0 10.0 2 SALVO .0625 LB AE/A 0.0 0.0 0.0 0.0 30.0 30.0 3 SALVO 0.125LB AE/A 0.0 0.0 0.0 0.0 60.0 40.0 4 SALVO 0.25 LB AE/A 0.0 0.0 0.0 0.090.0 90.0 5 SALVO 0.5 LB AE/A 0.0 0.0 0.0 0.0 90.0 90.0 6 SABER .0313 LBAE/A 0.0 0.0 0.0 0.0 5.0 0.0 7 SABER .0625 LB AE/A 0.0 0.0 0.0 0.0 10.05.0 8 SABER 0.125 LB AE/A 0.0 0.0 0.0 0.0 50.0 30.0 9 SABER 0.25 LB AE/A0.0 0.0 0.0 0.0 80.0 70.0 10 SABER 0.5 LB AE/A 0.0 0.0 0.0 0.0 90.0 85.011 PCC-1133 .0313 LB AE/A 0.0 0.0 0.0 0.0 20.0 10.0 12 PCC-1133 .0625 LBAE/A 0.0 0.0 0.0 0.0 30.0 20.0 13 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.050.0 50.0 14 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.0 85.0 80.0 15 PCC-11330.5 LB AE/A 0.0 0.0 0.0 0.0 90.0 90.0 16 PCC-1133 .0313 LB AE/A 0.0 0.00.0 0.0 50.0 15.0 PCC-1174 2 % V/V 17 PCC-1133 .0625 LB AE/A 0.0 0.0 0.00.0 50.0 30.0 PCC-1174 2 % V/V 18 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.070.0 60.0 PCC-1174 2 % V/V 19 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.0 95.095.0 PCC-1174 2 % V/V 20 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.0 98.0 95.0PCC-1174 2 % V/V 21 PCC-1133 .0313 LB AE/A 0.0 0.0 0.0 0.0 35.0 20.0SULFURIC ACID 2 % V/V 22 PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 40.030.0 SULFURIC ACID 2 % V/V 23 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.070.0 60.0 SULFURIC ACID 2 % V/V 24 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.095.0 90.0 SULFURIC ACID 2 % V/V 25 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.098.0 98.0 SULFURIC ACID 2 % V/V 26 PCC-1133 .0313 LB AE/A 0.0 0.0 0.00.0 30.0 30.0 PHOSPHORIC ACID 2 % V/V 27 PCC-1133 .0625 LB AE/A 0.0 0.00.0 0.0 40.0 30.0 PHOSPHORIC ACID 2 % V/V 28 PCC-1133 0.125 LB AE/A 0.00.0 0.0 0.0 65.0 60.0 PHOSPHORIC ACID 2 % V/V 29 PCC-1133 0.25 LB AE/A0.0 0.0 0.0 0.0 90.0 90.0 PHOSPHORIC ACID 2 % V/V 30 PCC-1133 0.5 LBAE/A 0.0 0.0 0.0 0.0 95.0 97.0 PHOSPHORIC ACID 2 % V/V 31 PCC-1133 .0313LB AE/A 0.0 0.0 0.0 0.0 28.3 10.0 LI-136 2 % V/V 32 PCC-1133 .0625 LBAE/A 0.0 0.0 0.0 0.0 50.0 40.0 LI-136 2 % V/V 33 PCC-1133 0.125 LB AE/A0.0 0.0 0.0 0.0 70.0 60.0 LI-136 2 % V/V 34 PCC-1133 0.25 LB AE/A 0.00.0 0.0 0.0 90.0 90.0 LI-136 2 % V/V 35 PCC-1133 0.5 LB AE/A 0.0 0.0 0.00.0 95.0 90.0 LI-136 2 % V/V 36 UNTREATED 0.0 0.0 0.0 0.0 0.0 0.0 DATAFOR EXPERIMENT 4 (ONE WEEK) Tame winter dry Rate Units corn oat Kochiawheat bean sunflower 1 PCC-1133 .0313 LB AE/A 0.0 0.0 0.0 0.0 7.0 7.0 2PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 30.0 20.0 3 PCC-1133 0.125 LBAE/A 0.0 0.0 0.0 0.0 50.0 40.0 4 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.060.0 60.0 5 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.0 80.0 80.0 6 PCC-1133.0313 LB AE/A 0.0 0.0 0.0 0.0 30.0 40.0 SULFURIC ACID 2 % V/V 7 PCC-1133.0625 LB AE/A 0.0 0.0 0.0 0.0 40.0 40.0 SULFURIC ACID 2 % V/V 8 PCC-11330.125 LB AE/A 0.0 0.0 0.0 0.0 80.0 60.0 SULFURIC ACID 2 % V/V 9 PCC-11330.25 LB AE/A 0.0 0.0 0.0 0.0 80.0 85.0 SULFURIC ACID 2 % V/V 10 PCC-11330.5 LB AE/A 0.0 0.0 0.0 0.0 95.0 90.0 SULFURIC ACID 2 % V/V 11 PCC-1133.0313 LB AE/A 0.0 0.0 0.0 0.0 60.0 50.0 HYDROCHLORIC ACID 2 % V/V 12PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 55.0 55.0 HYDROCHLORIC ACID 2 %V/V 13 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.0 65.0 70.0 HYDROCHLORICACID 2 % V/V 14 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.0 90.0 85.0HYDROCHLORIC ACID 2 % V/V 15 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.0 97.095.0 HYDROCHLORIC ACID 2 % V/V 16 PCC-1133 .0313 % V/V 0.0 0.0 0.0 0.030.0 30.0 NITRIC ACID 2 LB AE/A 17 PCC-1133 .0625 % V/V 0.0 0.0 0.0 0.060.0 60.0 NITRIC ACID 2 LB AE/A 18 PCC-1133 0.125 % V/V 0.0 0.0 0.0 0.060.0 60.0 NITRIC ACID 2 LB AE/A 19 PCC-1133 0.25 % V/V 0.0 0.0 0.0 0.083.3 85.0 NITRIC ACID 2 LB AE/A 20 PCC-1133 0.5 % V/V 0.0 0.0 0.0 0.088.3 90.0 NITRIC ACID 2 LB AE/A 21 PCC-1133 .0313 % V/V 0.0 0.0 0.0 0.040.0 20.0 GLACIAL ACETIC ACID 2 LB AE/A 22 PCC-1133 .0625 % V/V 0.0 0.00.0 0.0 50.0 30.0 GLACIAL ACETIC ACID 2 LB AE/A 23 PCC-1133 0.125 % V/V0.0 0.0 0.0 0.0 65.0 70.0 GLACIAL ACETIC ACID 2 LB AE/A 24 PCC-1133 0.25% V/V 0.0 0.0 0.0 0.0 65.0 70.0 GLACIAL ACETIC ACID 2 LB AE/A 25PCC-1133 0.5 % V/V 0.0 0.0 0.0 0.0 85.0 80.0 GLACIAL ACETIC ACID 2 % V/V26 PCC-1133 .0313 LB AE/A 0.0 0.0 0.0 0.0 50.0 40.0 PHOSPHORIC ACID 2 %V/V 27 PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 50.0 40.0 PHOSPHORIC ACID2 % V/V 28 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.0 85.0 60.0 PHOSPHORICACID 2 % V/V 29 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.0 90.0 80.0PHOSPHORIC ACID 2 % V/V 30 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.0 95.090.0 PHOSPHORIC ACID 2 % V/V 31 PCC-1133 .0313 LB AE/A 0.0 0.0 0.0 0.030.0 30.0 PERCHLORIC ACID 2 % V/V 32 PCC-1133 .0625 LB AE/A 0.0 0.0 0.00.0 40.0 30.0 PERCHLORIC ACID 2 % V/V 33 PCC-1133 0.125 LB AE/A 0.0 0.00.0 0.0 50.0 60.0 PERCHLORIC ACID 2 % V/V 34 PCC-1133 0.25 LB AE/A 0.00.0 0.0 0.0 75.0 60.0 PERCHLORIC ACID 2 % V/V 35 PCC-1133 0.5 LB AE/A0.0 0.0 0.0 0.0 85.0 70.0 PERCHLORIC ACID 2 % V/V 36 PCC-1133 .0313 LBAE/A 0.0 0.0 0.0 0.0 50.0 40.0 POLYPHOSPHORIC ACID 2 % V/V 37 PCC-1133.0625 LB AE/A 0.0 0.0 0.0 0.0 60.0 40.0 POLYPHOSPHORIC ACID 2 % V/V 38PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.0 60.0 60.0 POLYPHOSPHORIC ACID 2 %V/V 39 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.0 85.0 80.0 POLYPHOSPHORICACID 2 % V/V 40 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.0 90.0 90.0POLYPHOSPHORIC ACID 2 % V/V 41 SABER .0313 LB AE/A 0.0 0.0 0.0 0.0 10.05.0 42 SABER .0625 LB AE/A 0.0 0.0 0.0 0.0 30.0 10.0 43 SABER 0.125 LBAE/A 0.0 0.0 0.0 0.0 50.0 20.0 44 SABER 0.25 LB AE/A 0.0 0.0 0.0 0.060.0 60.0 45 SABER 0.5 LB AE/A 0.0 0.0 0.0 0.0 60.0 60.0 46 UNTREATED0.0 0.0 0.0 0.0 0.0 0.0 DATA FOR EXPERIMENT 4 (TWO WEEK) tame Rate Unitscorn oat kochia wheat dry bean sunflower 1 PCC-1133 .0313 LB AE/A 0.00.0 0.0 0.0 0.0 5.0 2 PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 40.0 20.0 3PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.0 50.0 40.0 4 PCC-1133 0.25 LB AE/A0.0 0.0 0.0 0.0 70.0 70.0 5 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.0 85.085.0 6 PCC-1133 .0313 LB AE/A 0.0 0.0 0.0 0.0 50.0 40.0 SULFURIC ACID 2% V/V 7 PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 60.0 60.0 SULFURIC ACID 2% V/V 8 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.0 80.0 70.0 SULFURIC ACID 2% V/V 9 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.0 90.0 80.0 SULFURIC ACID 2% V/V 10 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.0 95.0 88.3 SULFURIC ACID 2% V/V 11 PCC-1133 .0313 LB AE/A 0.0 0.0 0.0 0.0 60.0 50.0 HYDROCHLORICACID 2 % V/V 12 PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 60.0 50.0HYDROCHLORIC ACID 2 % V/V 13 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.0 70.070.0 HYDROCHLORIC ACID 2 % V/V 14 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.090.0 85.0 HYDROCHLORIC ACID 2 % V/V 15 PCC-1133 0.5 LB AE/A 0.0 0.0 0.00.0 99.0 97.0 HYDROCHLORIC ACID 2 % V/V 16 PCC-1133 .0313 % V/V 0.0 0.00.0 0.0 40.0 30.0 NITRIC ACID 2 LB AE/A 17 PCC-1133 .0625 % V/V 0.0 0.00.0 0.0 60.0 60.0 NITRIC ACID 2 LB AE/A 18 PCC-1133 0.125 % V/V 0.0 0.00.0 0.0 60.0 60.0 NITRIC ACID 2 LB AE/A 19 PCC-1133 0.25 % V/V 0.0 0.00.0 0.0 90.0 85.0 NITRIC ACID 2 LB AE/A 20 PCC-1133 0.5 % V/V 0.0 0.00.0 0.0 93.0 90.0 NITRIC ACID 2 LB AE/A 21 PCC-1133 .0313 % V/V 0.0 0.00.0 0.0 50.0 30.0 GLACIAL ACETIC ACID 2 LB AE/A 22 PCC-1133 .0625 % V/V0.0 0.0 0.0 0.0 50.0 30.0 GLACIAL ACETIC ACID 2 LB AE/A 23 PCC-11330.125 % V/V 0.0 0.0 0.0 0.0 65.0 65.0 GLACIAL ACETIC ACID 2 LB AE/A 24PCC-1133 0.25 % V/V 0.0 0.0 0.0 0.0 70.0 70.0 GLACIAL ACETIC ACID 2 LBAE/A 25 PCC-1133 0.5 % V/V 0.0 0.0 0.0 0.0 95.0 90.0 GLACIAL ACETIC ACID2 % V/V 26 PCC-1133 .0313 LB AE/A 0.0 0.0 0.0 0.0 60.0 50.0 PHOSPHORICACID 2 % V/V 27 PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 60.0 50.0PHOSPHORIC ACID 2 % V/V 28 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.0 85.070.0 PHOSPHORIC ACID 2 % V/V 29 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.090.0 80.0 PHOSPHORIC ACID 2 % V/V 30 PCC-1133 0.5 LB AE/A 0.0 0.0 0.00.0 97.0 93.0 PHOSPHORIC ACID 2 % V/V 31 PCC-1133 .0313 LB AE/A 0.0 0.00.0 0.0 40.0 30.0 PERCHLORIC ACID 2 % V/V 32 PCC-1133 .0625 LB AE/A 0.00.0 0.0 0.0 50.0 30.0 PERCHLORIC ACID 2 % V/V 33 PCC-1133 0.125 LB AE/A0.0 0.0 0.0 0.0 50.0 60.0 PERCHLORIC ACID 2 % V/V 34 PCC-1133 0.25 LBAE/A 0.0 0.0 0.0 0.0 75.0 70.0 PERCHLORIC ACID 2 % V/V 35 PCC-1133 0.5LB AE/A 0.0 0.0 0.0 0.0 85.0 80.0 PERCHLORIC ACID 2 % V/V 36 PCC-1133.0313 LB AE/A 0.0 0.0 0.0 0.0 50.0 20.0 POLYPHOSPHORIC ACID 2 % V/V 37PCC-1133 .0625 LB AE/A 0.0 0.0 0.0 0.0 55.0 40.0 POLYPHOSPHORIC ACID 2 %V/V 38 PCC-1133 0.125 LB AE/A 0.0 0.0 0.0 0.0 65.0 60.0 POLYPHOSPHORICACID 2 % V/V 39 PCC-1133 0.25 LB AE/A 0.0 0.0 0.0 0.0 85.0 85.0POLYPHOSPHORIC ACID 2 % V/V 40 PCC-1133 0.5 LB AE/A 0.0 0.0 0.0 0.0 91.790.0 POLYPHOSPHORIC ACID 2 % V/V 41 SABER .0313 LB AE/A 0.0 0.0 0.0 0.010.0 5.0 42 SABER .0625 LB AE/A 0.0 0.0 0.0 0.0 20.0 10.0 43 SABER 0.125LB AE/A 0.0 0.0 0.0 0.0 50.0 50.0 44 SABER 0.25 LB AE/A 0.0 0.0 0.0 0.070.0 70.0 45 SABER 0.5 LB AE/A 0.0 0.0 0.0 0.0 75.0 75.0 46 UNTREATED0.0 0.0 0.0 0.0 0.0 0.0 DATA FOR EXPERIMENT 5 (TWO WEEK) tame spring drysun- Rate Unit corn oat kochia wheat bean flower 1 PCC-1168 .0313 LBAE/A 0.0 0.0 0.0 0.0 5.0 0.0 2 PCC-1168 .0625 LB AE/A 0.0 0.0 0.0 10.030.0 20.0 3 PCC-1168 0.125 LB AE/A 20.0 20.0 0.0 40.0 50.0 60.0 4PCC-1168 0.25 LB AE/A 60.0 60.0 20.0 70.0 70.0 95.0 5 PCC-1168 0.5 LBAE/A 75.0 70.0 50.0 80.0 75.0 100.0 6 PCC-1168 .0313 LB AE/A 0.0 0.0 0.010.0 50.0 60.0 SULFURIC ACID 4 % V/V 7 PCC-1168 .0625 LB AE/A 10.0 30.00.0 30.0 70.0 90.0 SULFURIC ACID 4 % V/V 8 PCC-1168 0.125 LB AE/A 65.060.0 10.0 65.0 80.0 95.0 SULFURIC ACID 4 % V/V 9 PCC-1168 0.25 LB AE/A80.0 75.0 50.0 85.0 85.0 100.0 SULFURIC ACID 4 % V/V 10 PCC-1168 0.5 LBAE/A 100.0 100.0 95.0 100.0 98.0 100.0 SULFURIC ACID 4 % V/V 11 PCC-1168.0313 LB AE/A 0.0 0.0 0.0 0.0 30.0 20.0 HYDROCHLORIC ACID 4 % V/V 12PCC-1168 .0625 LB AE/A 0.0 0.0 0.0 10.0 50.0 65.0 HYDROCHLORIC ACID 4 %V/V 13 PCC-1168 0.125 LB AE/A 10.0 25.0 0.0 40.0 60.0 70.0 HYDROCHLORICACID 4 % V/V 14 PCC-1168 0.25 LB AE/A 75.0 70.0 10.0 60.0 80.0 90.0HYDROCHLORIC ACID 4 % V/V 15 PCC-1168 0.5 LB AE/A 80.0 90.0 60.0 90.093.0 100.0 HYDROCHLORIC ACID 4 % V/V 16 PCC-1168 .0313 % V/V 0.0 0.0 0.00.0 50.0 50.0 NITRIC ACID 4 LB AE/A 17 PCC-1168 .0625 % V/V 0.0 0.0 0.010.0 55.0 65.0 NITRIC ACID 4 LB AE/A 18 PCC-1168 0.125 % V/V 15.7 25.010.0 40.0 60.0 75.0 NITRIC ACID 4 LB AE/A 19 PCC-1168 0.25 % V/V 75.070.0 60.0 60.0 80.0 90.0 NITRIC ACID 4 LB AE/A 20 PCC-1168 0.5 % V/V80.0 85.0 60.0 85.0 90.0 98.0 NITRIC ACID 4 LB AE/A 21 PCC-1168 .0313 %V/V 0.0 0.0 0.0 0.0 0.0 0.0 GLACIAL ACETIC ACID 4 LB AE/A 22 PCC-1168.0625 % V/V 0.0 0.0 0.0 0.0 0.0 5.0 GLACIAL ACETIC ACID 4 LB AE/A 23PCC-1168 0.125 % V/V 10.0 20.0 0.0 36.7 30.0 40.0 GLACIAL ACETIC ACID 4LB AE/A 24 PCC-1168 0.25 % V/V 60.0 60.0 0.0 70.0 50.0 60.0 GLACIALACETIC ACID 4 LB AE/A 25 PCC-1168 0.5 % V/V 75.0 75.0 20.0 80.0 70.095.0 GLACIAL ACETIC ACID 4 % V/V 26 PCC-1168 .0313 LB AE/A 5.0 0.0 0.00.0 30.0 40.0 PHOSPHORIC ACID 4 % V/V 27 PCC-1168 .0625 LB AE/A 15.0 0.05.0 0.0 40.0 65.0 PHOSPHORIC ACID 4 % V/V 28 PCC-1168 0.125 LB AE/A 60.760.0 10.0 65.0 50.0 60.0 PHOSPHORIC ACID 4 % V/V 29 PCC-1168 0.25 LBAE/A 80.0 75.0 20.0 85.0 70.0 95.0 PHOSPHORIC ACID 4 % V/V 30 PCC-11680.5 LB AE/A 93.0 95.0 80.0 95.0 98.0 100.0 PHOSPHORIC ACID 4 % V/V 31PCC-1168 .0313 LB AE/A 0.0 0.0 0.0 0.0 40.0 40.0 PERCHLORIC ACID 4 % V/V32 PCC-1168 .0625 LB AE/A 20.0 20.0 0.0 20.0 50.0 60.0 PERCHLORIC ACID 4% V/V 33 PCC-1168 0.125 LB AE/A 65.0 60.0 20.0 60.0 55.0 60.0 PERCHLORICACID 4 % V/V 34 PCC-1168 0.25 LB AE/A 80.0 75.0 30.0 75.0 60.0 95.0PERCHLORIC ACID 4 % V/V 35 PCC-1168 0.5 LB AE/A 90.0 90.0 30.0 90.0 80.098.0 PERCHLORIC ACID 4 % V/V 36 PCC-1168 .0313 LB AE/A 70.0 70.0 0.060.0 50.0 50.0 POLYPHOSPHORIC ACID 4 % V/V 37 PCC-1168 .0625 LB AE/A75.0 75.0 0.0 75.0 55.0 65.0 POLYPHOSPHORIC ACID 4 % V/V 38 PCC-11680.125 LB AE/A 80.0 80.0 30.0 90.0 60.0 90.0 POLYPHOSPHORIC ACID 4 % V/V39 PCC-1168 0.25 LB AE/A 95.0 90.0 40.0 93.0 85.0 95.0 POLYPHOSPHORICACID 4 % V/V 40 PCC-1168 0.5 LB AE/A 98.0 95.0 80.0 95.0 90.0 100.0POLYPHOSPHORIC ACID 4 % V/V 41 UNTREATED 0.0 10.0 0.0 0.0 0.0 0.0

Examples 6-8

Examples of certain exemplary suspension concentrate herbicidecompositions according to the invention can contain 4 lb. imidazolinoneacid per gallon and can be prepared from ingredients including thosedescribed in Examples 6-8. In examples 6-8 “AI” means “activeingredient.”

Example 6

Example 6 is an exemplary suspension concentrate that includes a 4 lb.per gallon imidazolinone acid (imazethapyr acid), anionic surfactant,anionic dispersant, thickener, and anti-microbial agent. TABLE 6 Example6 Ingredients Ingredient % AI-Tech % Weight % AI Water 44.90 SAG 30Antifoam, Witco 0.3 Diethylene Glycol, freeze depressant, 5.00 DowMorwet EFW Wetter, Witco 1.00 Imazethapyr Acid 98.0 40.80 39.98 MorwetD425, dispersant, Witco 3.00 2% Kelzan - 0.5% Proxel Premix, 5.00thickener, Antimicrobial Total 100Morwet EFW is a mixture of alkyl napthonate sulfonates.

Example 7

Example 7 is an exemplary suspension concentrate that includes a 4 lb.per gallon imidazolinone acid (imazethapyr acid), acidifying agent,anionic surfactant, anionic dispersant, and thickener. TABLE 7 Example 7Ingredients Ingredient % AI-Tech % Weight % AI Water 44.70 SAG 30Antifoam, Witco 0.3 Diethylene Glycol, freeze 4.00 depressant, DowUnite, Loveland Industries, 1.00 surfactant & acidifier, anionicImazethapyr Acid 98.0 42.00 41.16 Soprophor FLK, Rhodia, Anionic 2.50dispersant 72% Phosphoric Acid, acidifier 0.50 Attaflow FL, Englehard,clay 5.00 thickener Total — 100 —

Example 8

Example 8 is an exemplary suspension concentrate that includes a 4 lb.per gallon imidazolinone acid (imazethapyr acid), nonionic surfactant,nonionic dispersant, thickener, and anti-microbial agent. TABLE Example8 Ingredients % Ingredient AI-Tech % Weight % AI Water 54.20 SAG 30Antifoam, Witco 0.3 Propylene Glycol, freeze 5.00 depressant, DowSurfonic L12-6, wetting 1.00 agent, nonionic, Huntsman Imazethapyr Acid98.0 31.00 30.38 Tersperse 4894, dispersant, 3.00 nonionic, Huntsman 2%Kelzan - 0.5% 5.00 Proxel Premix, thickener, Antimicrobial Total — 100 —

Examples 9-10

The following examples illustrate how exemplary suspension concentratesof the invention containing exemplary imidazolinone acid activeherbicide compounds, can be used to control plant growth. PCC-1190 andPCC-1189 are examples of suspension concentrates having 3 pounds ofimidazolinone acid active herbicide compound per gallon.

Materials and Methods:

Examples 9-10 represent experiments conducted to evaluate the efficacyof a variety of different types of herbicide formulations, includingformulations from suspension concentrates, and to evaluate the effect ofadding acids to the spray solution as an acidifying agent. Eachtreatment in the experiment was replicated three times. An untreatedcontrol was also included in the experiment.

Examples 9-10 were designed to determine the effect of adding fourdifferent acidifying agents (i.e., PCC-1174, LI-136, sulfuric acid, andphosphoric acid) to formulations of imidazolinone acid (PCC-1190 andPCC-1189) and the effect of applying each formulation at six differentrates (see data tables). These treatments were compared to PCC-1190 andPCC-1189 without the addition of an acidifying agent, a standardimidazolinone acid formulation (PURSUIT and SCEPTER), and an untreatedcontrol.

PCC-1189 Suspension Concentrate Formulation

PCC-1189 contains the active ingredient imazaquin acid. INGREDIENT %AI-Tech %/WT Water 54.20 SAG 30, OSI, Antifoam 0.30 Proplyene Glycol,Antifreeze 5.00 Surfonic L12-6, Huntsman, nonionic 1.00 wetting agentImazaquin Acid, Nat China, Active Ingredient 95.00 31.00 Tersperse 4894,Huntsman, nonionic 3.50 dispersant/wetter Attaflow FL 5.00 100.00Add in order listed to cowles high speed mixer stopping prior toAttaflow FL thickener addition.

-   -   Grind to 5-18 microns, 4 hrs in attritor, 60%.    -   Let down to mix tank with scales    -   Add calculated amount of thickener (accounting for amount of        batch that stays in the attritor) to milled liquid. Blend        moderately for 30 min.        PCC-1190 Suspension Concentrate Formulation

PCC-1190 contains the active ingredient imazethapyr acid. INGREDIENT %AI-Tech %/WT Water 54.20 SAG 30, OSI, Antifoam 0.30 Proplyene Glycol,Antifreeze 5.00 Surfonic L12-6, Huntsman, 1.00 nonionic wetting agentImazethapyr Acid, Nat China, 98.00 31.00 Active Ingredient Tersperse4894, Huntsman, 3.50 nonionic dispersant/wetter Attaflow FL 5.00 100.00Add in order listed to cowles high speed mixer stopping prior toAttaflow FL thickener addition.

-   -   Grind to 5-18 microns, 4 hrs in attritor, 60%.    -   Let down to mix tank with scales    -   Add calculated amount of thickener (accounting for amount of        batch that stays in the attritor) to milled liquid. Blend        moderately for 30 min.

PURSUIT® is a commercially available product containing the activeingredient imazethapyr acid. PURSUIT® is formulated as a 2SL (“2SL”means a “two pound per gallon soluble liquid”). SCEPTER® is acommercially available product containing the active ingredientimazaquin acid.

Acidifying Agents

Sulfuric Acid—0.9%

Phosphoric Acid—0.9%

PCC-1174 Acidifying Agent, see supra.

LI-136 acidifying agent, see supra

Procedure

For the experiments, greenhouse flats 26 cm by 6 cm deep were filledwith Metro Mix 350 potting soil. The soil was pre-wetted before fillingthe flats. Six furrows were pressed into the soil in each flat using acustom designed form. Corn, tame oats, velvet leaf (not used in Example10), wheat, pinto beans, and sunflower were planted in each tray. Onespecies was planted in each of the six rows in each flat. Five seedswere planted in each row of corn, pinto bean, and sunflower. Six seedswere planted in each row of tame oat and wheat. Because velvet leafseeds were so small, the seeds were sprinkled in each row and the numberof such seeds were not counted. Each flat was covered with 2 cm of MetroMix 350 potting soil and placed in the greenhouse. Greenhouse conditionswere 28/20 C day/night temperatures and 16/8 h day/night periods. Lightwas supplemented with 400 W sodium halide lights. The plants wereallowed to germinate and grow in the greenhouse for 2 weeks and thentreated. Treatments were mixed using serial dilutions. Each dilutionreduced the herbicide rate by one half. All acidifying agents (e.g.,PCC-1174, LI-136, sulfuric acid, and phosphoric acid) were calculatedand mixed to provide acid concentrations of 0.9%.

After mixing, the pH of the spray solution of each treatment wasmeasured with a VWR Scientific model 8005 pH meter. The pH was measuredto determine if the acid used or the amount of acid added was sufficientto lower the pH below the pKa of the acid herbicides used.

At the time of treatment, crops were at the following stages: corn—2 to3 lf, tame oat—2 to 3 lf, velvet leaf—2 lf (not used in Example 10),pinto bean—2-3 If, wheat—4 to 5 lf, and sunflower—2 lf. Plants weretreated using a greenhouse track sprayer equipped with an 8001E nozzleand calibrated to deliver 140 L ha-1 at the height of the crop canopy.Each treatment was simultaneously applied to three trays of plants, onefor each replicate. After treatment, the plants were left in the headhouse to dry and then transferred to the greenhouse. Plants in eachtreatment were evaluated visually for injury 1 week and 2 weeks aftertreatment.

Summary of Variables of Example 9

Volumes of Herbicide Acid each Acid Rate (lb Treatments (v/v %)Herbicide AE/A) Plants Reps PCC-1174 2 PCC-1190 1 Corn, 3 Sulfuric 0.5Tame oat, Phosphoric 0.25 Velvet leaf, wheat LI-136 0.125 0.063 Pintobean, 0.0313 Sunflower

Following are data that illustrate the efficacy of various herbicidecompositions of Examples 9-10 and Summary of Variables of Example 10.The injury caused by the herbicide treatment was rated visually. Plantswere observed and compared to the untreated control. All the plants ofeach species in each replication were given a single rating. A rating of0=no injury—the plants look the same as the untreated. A rating of100=dead—usually highly necrotic, brown and no chance of producing seed.

Each of the acids was combined with the PCC-1190 or PCC-1189 herbicidecompositions to form a solution that contains 2 percent by volume of agiven 0.9% (of the acid) concentrated acidifying agent (e.g., PCC-1174,LI-136, sulfuric acid, and phosphoric acid), as indicated, and such thatthe pH of the herbicide composition was below the pKa of the particularherbicide compound.

The ingredients of the herbicide compositions as applied are listed inthe following tables, and were diluted with water and used at the ratesindicated for herbicide ingredients and acidifying agents. Tame VelvetPinto Herbicide Rate Units Corn Oat Leaf Wheat Bean Sunflower Data forExample 9 (One Week) 1 PURSUIT .0313 LB AE/A 0.0 10.0 50.0 10.0 10.050.0 2 PURSUIT 0.063 LB AE/A 0.0 20.0 50.0 20.0 10.0 50.0 3 PURSUIT0.125 LB AE/A 0.0 30.0 50.0 20.0 20.0 50.0 4 PURSUIT 0.25 LB AE/A 0.050.0 50.0 20.0 30.0 70.0 5 PURSUIT 0.5 LB AE/A 0.0 60.0 50.0 30.0 40.090.0 6 PURSUIT 1 LB AE/A 10.0 60.0 50.0 50.0 40.0 98.0 7 PCC-1190 .0313LB AE/A 0.0 10.0 50.0 10.0 10.0 50.0 8 PCC-1190 0.063 LB AE/A 0.0 20.050.0 20.0 20.0 50.0 9 PCC-1190 0.125 LB AE/A 0.0 30.0 50.0 20.0 20.060.0 10 PCC-1190 0.25 LB AE/A 0.0 50.0 50.0 30.0 40.0 70.0 11 PCC-11900.5 LB AE/A 0.0 60.0 50.0 40.0 40.0 90.0 12 PCC-1190 1 LB E/A 0.0 60.050.0 50.0 60.0 98.0 13 PCC-1190 .0313 LB AE/A 0.0 20.0 50.0 10.0 10.050.0 PCC-1174 2 % V/V 14 PCC-1190 0.063 LB AE/A 0.0 20.0 50.0 10.0 10.050.0 PCC-1174 2 % V/V 15 PCC-1190 .0125 LB AE/A 0.0 30.0 50.0 20.0 20.070.0 PCC-1174 2 % V/V 16 PCC-1190 0.25 LB AE/A 0.0 50.0 50.0 20.0 30.080.0 PCC-1174 2 % V/V 17 PCC-1190 0.5 LB AE/A 0.0 60.0 50.0 30.0 40.098.0 PCC-1174 2 % V/V 18 PCC-1190 1 LB AE/A 0.0 60.0 50.0 50.0 50.0 98.0PCC-1174 2 % V/V 19 PCC-1190 .0313 LB AE/A 0.0 10.0 50.0 10.0 10.0 40.0SULFURIC ACID 2 % V/V 20 PCC-1190 0.063 LB AE/A 0.0 20.0 50.0 20.0 20.050.0 SULFURIC ACID 2 % V/V 21 PCC-1190 .0125 LB AE/A 0.0 30.0 50.0 20.030.0 50.0 SULFURIC ACID 2 % V/V 22 PCC-1190 0.25 LB AE/A 0.0 40.0 50.030.0 50.0 80.0 SULFURIC ACID 2 % V/V 23 PCC-1190 0.5 LB AE/A 0.0 50.060.0 50.0 50.0 90.0 SULFURIC ACID 2 % V/V 24 PCC-1190 1 LB AE/A 0.0 60.060.0 50.0 60.0 98.0 SULFURIC ACID 2 % V/V 25 PCC-1190 .0313 LB AE/A 0.010.0 50.0 10.0 10.0 50.0 PHOSPHORIC ACID 2 % V/V 26 PCC-1190 0.063 LBAE/A 0.0 20.0 50.0 10.0 10.0 50.0 PHOSPHORIC ACID 2 % V/V 27 PCC-1190.0125 LB AE/A 0.0 20.0 50.0 10.0 20.0 50.0 PHOSPHORIC ACID 2 % V/V 28PCC-1190 0.25 LB AE/A 0.0 30.0 50.0 30.0 30.0 50.0 PHOSPHORIC ACID 2 %V/V 29 PCC-1190 0.5 LB AE/A 0.0 40.0 50.0 40.0 40.0 70.0 PHOSPHORIC ACID2 % V/V 30 PCC-1190 1 LB AE/A 0.0 40.0 50.0 50.0 50.0 90.0 PHOSPHORICACID 2 % V/V 31 PCC-1190 .0313 LB AE/A 0.0 10.0 50.0 10.0 10.0 50.0 LI136 2 % V/V 32 PCC-1190 0.063 LB AE/A 0.0 10.0 50.0 10.0 10.0 50.0 LI136 2 % V/V 33 PCC-1190 .0125 LB AE/A 0.0 20.0 50.0 20.0 20.0 50.0 LI136 2 % V/V 34 PCC-1190 0.25 LB AE/A 0.0 40.0 50.0 20.0 30.0 70.0 LI 1362 % V/V 35 PCC-1190 0.5 LB AE/A 0.0 40.0 50.0 30.0 30.0 70.0 LI 136 2 %V/V 36 PCC-1190 1 LB AE/A 0.0 50.0 50.0 40.0 40.0 95.0 LI 136 2 % V/V 37UNTREATED 0.0 0.0 0.0 0.0 0.0 0.0 Data for Example 9 (Two Week) 1PURSUIT .0313 LB AE/A 20.0 20.0 50.0 20.0 30.0 50.0 2 PURSUIT 0.063 LBAE/A 20.0 20.0 50.0 20.0 30.0 50.0 3 PURSUIT 0.125 LB AE/A 20.0 40.050.0 30.0 35.0 50.0 4 PURSUIT 0.25 LB AE/A 20.0 50.0 60.0 40.0 35.0 70.05 PURSUIT 0.5 LB AE/A 20.0 70.0 60.0 70.0 45.0 95.0 6 PURSUIT 1 LB AE/A20.0 80.0 70.0 75.0 55.0 100.0 7 PCC-1190 .0313 LB AE/A 10.0 20.0 50.020.0 25.0 50.0 8 PCC-1190 0.063 LB AE/A 20.0 30.0 50.0 30.0 35.0 70.0 9PCC-1190 0.125 LB AE/A 30.0 60.0 50.0 30.0 35.0 70.0 10 PCC-1190 0.25 LBAE/A 20.0 70.0 60.0 50.0 40.0 90.0 11 PCC-1190 0.5 LB AE/A 20.0 70.060.0 70.0 50.0 95.0 12 PCC-1190 1 LB AE/A 20.0 85.0 70.0 75.0 65.0 100.013 PCC-1190 .0313 LB AE/A 10.0 50.0 50.0 25.0 30.0 70.0 PCC-1174 2 % V/V14 PCC-1190 0.063 LB AE/A 10.0 50.0 50.0 40.0 30.0 80.0 PCC-1174 2 % V/V15 PCC-1190 .0125 LB AE/A 10.0 60.0 50.0 40.0 30.0 85.0 PCC-1174 2 % V/V16 PCC-1190 0.25 LB AE/A 10.0 70.0 60.0 50.0 50.0 95.0 PCC-1174 2 % V/V17 PCC-1190 0.5 LB AE/A 20.0 80.0 60.0 75.0 50.0 95.0 PCC-1174 2 % V/V18 PCC-1190 1 LB AE/A 20.0 90.0 70.0 85.0 70.0 100.0 PCC-1174 2 % V/V 19PCC-1190 .0313 LB AE/A 20.0 50.0 50.0 25.0 30.0 70.0 SULFURIC ACID 2 %V/V 20 PCC-1190 0.063 LB AE/A 30.0 50.0 50.0 40.0 40.0 80.0 SULFURICACID 2 % V/V 21 PCC-1190 .0125 LB AE/A 23.3 60.0 50.0 40.0 35.0 85.0SULFURIC ACID 2 % V/V 22 PCC-1190 0.25 LB AE/A 20.0 70.0 60.0 50.0 50.095.0 SULFURIC ACID 2 % V/V 23 PCC-1190 0.5 LB AE/A 10.0 80.0 65.0 75.065.0 95.0 SULFURIC ACID 2 % V/V 24 PCC-1190 1 LB AE/A 20.0 95.0 70.085.0 80.0 100.0 SULFURIC ACID 2 % V/V 25 PCC-1190 .0313 LB AE/A 10.050.0 50.0 25.0 30.0 70.0 PHOSPHORIC ACID 2 % V/V 26 PCC-1190 0.063 LBAE/A 20.0 50.0 50.0 40.0 30.0 80.0 PHOSPHORIC ACID 2 % V/V 27 PCC-1190.0125 LB AE/A 10.0 56.7 50.0 35.0 30.0 85.0 PHOSPHORIC ACID 2 % V/V 28PCC-1190 0.25 LB AE/A 20.0 66.7 60.0 50.0 40.0 95.0 PHOSPHORIC ACID 2 %V/V 29 PCC-1190 0.5 LB AE/A 20.0 70.0 60.0 75.0 50.0 95.0 PHOSPHORICACID 2 % V/V 30 PCC-1190 1 LB AE/A 20.0 76.7 70.0 75.0 70.0 100.0PHOSPHORIC ACID 2 % V/V 31 PCC-1190 .0313 LB AE/A 10.0 46.7 50.0 20.025.0 60.0 LI 136 2 % V/V 32 PCC-1190 0.063 LB AE/A 0.0 30.0 50.0 30.025.0 80.0 LI 136 2 % V/V 33 PCC-1190 .0125 LB AE/A 10.0 30.0 50.0 30.030.0 70.0 LI 136 2 % V/V 34 PCC-1190 0.25 LB AE/A 15.0 50.0 60.0 35.030.0 85.0 LI 136 2 % V/V 35 PCC-1190 0.5 LB AE/A 20.0 63.3 60.0 50.045.0 90.0 LI 136 2 % V/V 36 PCC-1190 1 LB AE/A 20.0 80.0 70.0 60.0 55.096.7 LI 136 2 % V/V 37 UNTREATED 0.0 0.0 0.0 0.0 0.0 0.0

Summary of Variables of Example 10

Volumes Herbicide of each Acid Rate (lb Acid Treatments (v/v %)Herbicide AE/A) Plants Reps PCC-1174 2 PCC-1189 0.0155 Corn, 3 SULFURIC0.031 Tame oat, PHOSPHORIC 0.0613 Wheat, LI-136 0.1225 0.245 Pinto bean,0.49 Sunflower Data for Example 10 (Two Week) Tame Pinto Sun- HerbicideRate Unit Corn Oat Wheat Bean flower 1 SCEPTOR .0155 LB AE/A 0.0 0.0 0.00.0 0.0 2 SCEPTOR 0.031 LB AE/A 0.0 0.0 10.0 20.0 30.0 3 SCEPTOR .0613LB AE/A 0.0 0.0 0.0 10.0 10.0 4 SCEPTOR .1225 LB AE/A 10.0 0.0 0.0 10.030.0 5 SCEPTOR 0.245 LB AE/A 10.0 0.0 0.0 20.0 60.0 6 SCEPTOR 0.49 LBAE/A 20.0 10.0 10.0 20.0 60.0 7 PCC-1189 .0155 LB AE/A 30.0 10.0 10.00.0 0.0 8 PCC-1189 0.031 LB AE/A 0.0 0.0 0.0 10.0 10.0 9 PCC-1189 .0613LB AE/A 20.0 10.0 0.0 10.0 10.0 10 PCC-1189 .1225 LB AE/A 20.0 10.0 10.010.0 60.0 11 PCC-1189 0.245 LB AE/A 40.0 20.0 10.0 20.0 60.0 12 PCC-11890.49 LB AE/A 30.0 10.0 10.0 10.0 70.0 13 PCC-1189 .0155 LB AE/A 30.020.0 10.0 10.0 20.0 13 PCC-1174 2 % V/V 30.0 20.0 10.0 10.0 20.0 14PCC-1189 0.031 LB AE/A 10.0 20.0 10.0 20.0 70.0 14 PCC-1174 2 % V/V 10.020.0 10.0 20.0 70.0 15 PCC-1189 .0613 LB AE/A 30.0 30.0 20.0 30.0 60.015 PCC-1174 2 % V/V 30.0 30.0 20.0 30.0 60.0 16 PCC-1189 .1225 LB AE/A40.0 30.0 20.0 30.0 70.0 16 PCC-1174 2 % V/V 40.0 30.0 20.0 30.0 70.0 17PCC-1189 0.245 LB AE/A 50.0 30.0 20.0 40.0 60.0 17 PCC-1174 2 % V/V 50.030.0 20.0 40.0 60.0 18 PCC-1189 0.49 LB AE/A 50.0 10.0 10.0 60.0 90.0 18PCC-1174 2 % V/V 50.0 10.0 10.0 60.0 90.0 19 PCC-1189 .0155 LB AE/A 10.00.0 0.0 10.0 30.0 19 SULFURIC ACID 2 % V/V 10.0 0.0 0.0 10.0 30.0 20PCC-1189 0.031 LB AE/A 20.0 0.0 0.0 10.0 30.0 20 SULFURIC ACID 2 % V/V20.0 0.0 0.0 10.0 30.0 21 PCC-1189 .0613 LB AE/A 10.0 0.0 0.0 0.0 40.021 SULFURIC ACID 2 % V/V 10.0 0.0 0.0 0.0 40.0 22 PCC-1189 .1225 LB AE/A10.0 0.0 0.0 10.0 40.0 22 SULFURIC ACID 2 % V/V 10.0 0.0 0.0 10.0 40.023 PCC-1189 0.245 LB AE/A 20.0 0.0 0.0 20.0 60.0 23 SULFURIC ACID 2 %V/V 20.0 0.0 0.0 20.0 60.0 24 PCC-1189 0.49 LB AE/A 20.0 10.0 10.0 30.080.0 24 SULFURIC ACID 2 % V/V 20.0 10.0 10.0 30.0 80.0 25 PCC-1189 .0155LB AE/A 10.0 0.0 0.0 10.0 50.0 25 PHOSPHORIC ACID 2 % V/V 10.0 0.0 0.010.0 50.0 26 PCC-1189 0.031 LB AE/A 10.0 0.0 0.0 20.0 50.0 26 PHOSPHORICACID 2 % V/V 10.0 0.0 0.0 20.0 50.0 27 PCC-1189 .0613 LB AE/A 15.0 0.00.0 30.0 40.0 27 PHOSPHORIC ACID 2 % V/V 15.0 0.0 0.0 30.0 40.0 28PCC-1189 .1225 LB AE/A 10.0 0.0 0.0 25.0 50.0 28 PHOSPHORIC ACID 2 % V/V10.0 0.0 0.0 25.0 50.0 29 PCC-1189 0.245 3 AE/A 10.0 0.0 0.0 30.0 60.029 PHOSPHORIC ACID 2 V/V 10.0 0.0 0.0 30.0 60.0 30 PCC-1189 0.49 3 AE/A20.0 0.0 0.0 30.0 50.0 30 PHOSPHORIC ACID 2 V/V 20.0 0.0 0.0 30.0 50.031 PCC-1189 .0155 3 AE/A 20.0 0.0 0.0 10.0 20.0 31 LI136 2 V/V 20.0 0.00.0 10.0 20.0 32 PCC-1189 0.031 3 AE/A 20.0 0.0 0.0 10.0 10.0 32 LI136 2V/V 20.0 0.0 0.0 10.0 10.0 33 PCC-1189 .0613 3 AE/A 10.0 0.0 0.0 10.030.0 33 LI136 2 V/V 10.0 0.0 0.0 10.0 30.0 34 PCC-1189 .1225 3 AE/A 30.020.0 20.0 30.0 20.0 34 LI136 2 V/V 30.0 20.0 20.0 30.0 20.0 35 PCC-11890.245 3 AE/A 30.0 10.0 10.0 30.0 40.0 35 LI136 2 V/V 30.0 10.0 10.0 30.040.0 36 PCC-1189 0.49 3 AE/A 10.0 0.0 0.0 20.0 70.0 36 LI136 2 V/V 10.00.0 0.0 20.0 70.0 37 Untreated 0.0 0.0 0.0 0.0 0.0

Following are still other examples of herbicide compositions containingherbicide compound in acid form, that can be used according to thepresent description in combination with an acidifying agent. The firstis a wettable powder and the second and third are microemulsion-formingconcentrates. pcc1209 quizalofop-p, 80% - Wettable Powder 90%Quizalofop-p Acid 88.8% Morwet EFW, wetter, sulfonate 1.5 Polfon H,lignin, dispersant 2.0 Morwest D425, dispersant, urea-form condensate2.0 Wessalon 50S, grinding aid, silica 1.0 Kaolin Clay, diluent 4.7 UHS3 way acid mix MFC Surfonic L12-6, alcohol ethoxylate 64.9 SurfonicPE-1218, phosphate ester 8.0 2,4D acid 17.8 MCPA acid 7.6 Dicamba acid1.6 SAG 10, antifoam 0.1 pcc 1154, 1 lb/gal each 2,4D Acid, FluroxypyrAcid MFC Tomadol 1-5, alcohol ethoxylate 13.9 Tomadol 1-7, alcoholethoxylate 13.9 Surfonic T-15, tallow amine 49.9 Fluroxypyr acid 11.12,4D acid 11.1 SAG 10 Antifoam 0.1

1. A method of controlling plant growth, the method comprising:preparing a herbicide composition, by providing a herbicide concentratecomposition comprising herbicide compound in acid form other thanglyphosate acid, combining the herbicide concentrate composition withacidifying agent and water to form a herbicide application compositionhaving a pH below the pKa of the herbicide compound in acid form, andapplying the herbicide application composition to control plant growth.2. The method of claim 1 comprising providing the herbicide concentratecomposition, adding acidifying agent to the herbicide concentratecomposition, and adding water to the herbicide concentrate composition.3. The method of claim 2 wherein the herbicide concentrate compositionis selected from the group consisting of: a microemulsion-formingconcentrate, a microemulsion, and a suspension concentrate.
 4. Themethod of claim 1 comprising combining the herbicide concentratecomposition with water and acidifying agent in a spray tank to form theherbicide application composition.
 5. The method of claim 1 wherein theherbicide concentrate composition is selected from the group consistingof: a microemulsion-forming concentrate, a microemulsion, and asuspension concentrate.
 6. The method of claim 1 wherein the pH of theherbicide application composition as applied is below
 7. 7. The methodof claim 1 wherein the pKa of the herbicide compound is below
 5. 8. Themethod of claim 1 wherein the acidifying agent is sulfuric acid.
 9. Themethod of claim 1 wherein the acidifying agent is selected from thegroup consisting of: hydrochloric acid, nitric acid, acetic acid,phosphoric acid, polyphosphoric acid, perchloric acid, and combinationsthereof, and the herbicide composition does not include sulfuric acid.10. The method of claim 1 wherein the acidifying agent is selected fromthe group consisting of: sulfuric acid, hydrochloric acid, nitric acid,acetic acid, phosphoric acid, perchloric acid, polyphosphoric acid, andcombinations thereof.
 11. The method of claim 1 wherein the acidifyingagent is selected from the group consisting of: sulfuric acid,hydrochloric acid, nitric acid, acetic acid, phosphoric acid, perchloricacid, and polyphosphoric acid, and the composition does not include asulfuric acid adduct of the formula:

wherein X is chalcogen, and each of R₁, R₂, and R ₃ is independentlyselected from hydrogen and organic radicals.
 12. The method of claim 1wherein the herbicide compound in acid form is chosen from the groupconsisting of: a phenoxy herbicide, a pyridine herbicide, a benzoic acidherbicide, a quinolinic acid herbicide, an aryloxy phenoxy propionicacid herbicide, and combinations thereof.
 13. The method of claim 1wherein the herbicide compound in acid form is selected from the groupconsisting of 2,4-dichlorophenoxyacetic acid, dicamba acid(3,6-dichloro-O-anixic acid), 4-methyl-4-chloropnenoxyacetic acid,2(-2-methyl-4-chlorophenoxy)propionic acid,3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr acid), fluazifopacid, [(4-amino-3,5-dichloro-6-fluoro-2-pyridinyl)oxy]acetic acid(fluoroxypyr acid), and combinations thereof.
 14. The method of claim 1wherein the herbicide application composition further comprisesglyphosate acid.
 15. The method of claim 1 wherein the herbicideapplication composition does not include glyphosate acid.
 16. The methodof claim 1 wherein the herbicide concentrate composition containsessentially no organic solvent.